Researcher Database

Futoshi Nakamura
Research Faculty of Agriculture Fundamental AgriScience Research Forest Science
Professor

Researcher Profile and Settings

Affiliation

  • Research Faculty of Agriculture Fundamental AgriScience Research Forest Science

Job Title

  • Professor

URL

J-Global ID

Research Interests

  • Ecosystem Management   Landscape Ecology   Stream Ecology   

Research Areas

  • Life sciences / Forest science
  • Life sciences / Ecology and environmental science

Academic & Professional Experience

  • 2006 - Today - 大学院農学研究院環境資源学専攻森林管理保全学講座森林生態系管理学分野教授 教授
  • 2000 - 2006 大学院農学研究科環境資源学専攻森林管理保全学講座森林施業計画学分野教授 教授
  • 2000 - 2006 Professor
  • 2006 - Professor
  • 1992 - 2000 大学院農学研究科環境資源学専攻森林管理保全学講座砂防学分野助教授 助教授
  • 1992 - 2000 Associate Professor
  • 1990 - 1992 オレゴン州立大学林学部森林科学科 客員Assistant Professor
  • 1989 - 1992 大学院農学研究科林学専攻砂防学講座講師 講師
  • 1989 - 1992 Lecturer
  • 1984 - 1989 農学部林学科砂防工学講座助手 助手
  • 1984 - 1989 Research Associate

Education

  • 1987 -   農学博士(論文)
  •        - 1984  Hokkaido University
  •        - 1984  Hokkaido University  Graduate School, Division of Agriculture
  • 1981 - 1983  Hokkaido University
  •        - 1983  Hokkaido University  Graduate School, Division of Agriculture
  • 1977 - 1981  Hokkaido University  Faculty of Agriculture
  •        - 1981  Hokkaido University  Faculty of Agriculture

Association Memberships

  • Landscape and Ecological Engineering   日本学術会議研究連絡委員会委員(森林工学研究連絡委員会   応用生態工学会   日本森林学会   THE ECOLOGICAL SOCIETY OF JAPAN   

Research Activities

Published Papers

  • Nanoka Teshima, Kazuhiro Kawamura, Takumi Akasaka, Satoshi Yamanaka, Futoshi Nakamura
    Forest Ecology and Management 519 120300 - 120300 0378-1127 2022/09
  • Kei Uchida, Azumi Okazaki, Takumi Akasaka, Junjiro N. Negishi, Futoshi Nakamura
    Journal of Environmental Management 317 115467 - 115467 0301-4797 2022/09
  • Takumi Akasaka, Terutaka Mori, Nobuo Ishiyama, Yuya Takekawa, Tomonori Kawamoto, Mikio Inoue, Hiromune Mitsuhashi, Yoichi Kawaguchi, Hidetaka Ichiyanagi, Norio Onikura, Yo Miyake, Izumi Katano, Munemitsu Akasaka, Futoshi Nakamura
    DIVERSITY AND DISTRIBUTIONS 28 (6) 1191 - 1201 1366-9516 2022/06 
    Aim Natural disaster risk reduction (DRR) is becoming a more important function of protected area (PAs) for current and future global warming. However, biodiversity conservation and DRR have been handled separately and their interrelationship has not been explicitly addressed. This is mainly because, due of prevailing strategies and criteria for PA placement, a large proportion of PAs are currently located far from human-occupied areas, and habitats in human-occupied areas have been largely ignored as potential sites for conservation despite their high biodiversity. If intensely developed lowland areas with high flooding risk overlap with important sites for biodiversity conservation, it would be reasonable to try to harmonize biodiversity conservation and human development in human-inhabited lowland areas. Here, we examined whether extant PAs can conserve macroinvertebrate and freshwater fish biodiversity and whether human-inhabited lowland flood risk management sites might be suitable to designate as freshwater protected areas (FPAs). Location Across Japan. Methods We examined whether extant PAs can conserve macroinvertebrate and freshwater fish biodiversity and analysed the relationship between candidate sites for new FPAs and flood disaster risk and land use intensity at a national scale across Japan based on distribution data for 131 freshwater fish species and 1395 macroinvertebrate species. Results We found that extant PAs overlapped with approximately 30% of conservation-priority grid cells (1 km(2)) for both taxa. Particularly for red-listed species, only one species of freshwater fish and three species of macroinvertebrate achieved the representation target within extant PAs. Moreover, more than 40% of candidate conservation-priority grid cells were located in flood risk and human-occupied areas for both taxa. Main conclusions Floodplain conservation provides suitable habitat for many freshwater organisms and helps control floodwaters, so establishing new FPAs in areas with high flood risk could be a win-win strategy for conserving freshwater biodiversity and enhancing ecosystem-based DRR (eco-DRR).
  • Munehiro Kitazawa, Yuichi Yamaura, Masayuki Senzaki, Masashi Hanioka, Haruka Ohashi, Michio Oguro, Tetsuya Matsui, Futoshi Nakamura
    PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES 289 (1975) 0962-8452 2022/05 
    Land cover change for agriculture is thought to be a major threat to global biodiversity. However, its ecological impact has rarely been quantified in the Northern Hemisphere, as broad-scale conversion to farmland mainly occurred until the 1400s-1700s in the region, limiting the availability of sufficient data. The Ishikari Lowland in Hokkaido, Japan, offers an excellent opportunity to address this issue, as hunter-gatherer lifestyles dominated this region until the mid-nineteenth century and land cover maps are available for the period of land cover changes (i.e. 1850-2016). Using these maps and a hierarchical community model of relationships between breeding bird abundance and land cover types, we estimated that broad-scale land cover change over a 166-year period was associated with more than 70% decline in both potential species richness and abundance of avian communities. We estimated that the abundance of wetland and forest species declined by greater than 88%, whereas that of bare-ground/farmland species increased by more than 50%. Our results suggest that broad-scale land cover change for agriculture has led to drastic reductions in wetland and forest species and promoted changes in community composition in large parts of the Northern Hemisphere. This study provides potential baseline information that could inform future conservation policies.
  • Wataru Hotta, Junko Morimoto, Chihiro Haga, Satoshi N. Suzuki, Takahiro Inoue, Takanori Matsui, Toshiaki Owari, Hideaki Shibata, Futoshi Nakamura
    Forest Ecology and Management 502 119728 - 119728 0378-1127 2021/12
  • Junjiro N. Negishi, Tomohiro Nakagawa, Futoshi Nakamura
    Aquatic Ecology 1386-2588 2021/10/13
  • Souta Nakajima, Masanao Sueyoshi, Shun K. Hirota, Nobuo Ishiyama, Ayumi Matsuo, Yoshihisa Suyama, Futoshi Nakamura
    Heredity 127 (4) 413 - 422 0018-067X 2021/10 [Refereed]
     
    A key piece of information for ecosystem management is the relationship between the environment and population genetic structure. However, it is difficult to clearly quantify the effects of environmental factors on genetic differentiation because of spatial autocorrelation and analytical problems. In this study, we focused on stream ecosystems and the environmental heterogeneity caused by groundwater and constructed a sampling design in which geographic distance and environmental differences are not correlated. Using multiplexed ISSR genotyping by sequencing (MIG-seq) method, a fine-scale population genetics study was conducted in fluvial sculpin Cottus nozawae, for which summer water temperature is the determinant factor in distribution and survival. There was a clear genetic structure in the watershed. Although a significant isolation-by-distance pattern was detected in the watershed, there was no association between genetic differentiation and water temperature. Instead, asymmetric gene flow from relatively low-temperature streams to high-temperature streams was detected, indicating the importance of low-temperature streams and continuous habitats. The groundwater-focused sampling strategy yielded insightful results for conservation.
  • Kazuki Miura, Nobuo Ishiyama, Junjiro N. Negishi, Daisetsu Ito, Keita Kawajiri, Hokuto Izumi, Takahiro Inoue, Masahiro Nakaoka, Futoshi Nakamura
    2021/09/23 
    AbstractMultiple stressors can interactively affect the population of organisms; however, the process by which they affect recruitment efficiency remains unclear for empirical populations. Recruitment efficiency can be regulated at multiple stages of life, particularly in organisms with complex life cycles. Understanding the interactive effects of multiple stressors on recruitment efficiency and determining the bottleneck life stages is imperative for species conservation. The proportion of <20-year-old juveniles of the endangered freshwater pearl mussel Margaritifera togakushiensis, which has an obligate parasitic larval stage, was investigated in 24 rivers from eastern Hokkaido, northern Japan to reveal the influence of nutrients, fine sediment, and their combined effects on juvenile recruitment efficiency. The following indices for recruitment at adult, parasitic, and post-parasitic juvenile stages were obtained from 11 of these rivers: gravid female density, glochidia density (the number of glochidia infections per stream area), and juvenile survival rate. This study explored the bottleneck stages of recruitment efficiency and the interactive effects of the two stressors on these stages. Twenty-four population status assessments determined that the proportion of juveniles ranged from 0.00 to 0.53, and juveniles were absent from four rivers. The results showed that the parasitic and post-parasitic juvenile stages were bottlenecks for recruitment efficiency. Juvenile survival rates had a more significant positive effect on recruitment efficiency in rivers with a high glochidia density. Juvenile survival rate was decreased by the synergistic interaction of nutrients and fine sediment, although factors limiting glochidia density were not found. The nutrient concentration of rivers in the study region was well explained by the proportion of agricultural land cover and urban areas in the watersheds, but no relationship was detected between fine sediment abundance and land use. This study suggests that nutrient management at a catchment scale can be effective for re-establishing the recruitment of M. togakushiensis, particularly in rivers with a high content of fine sediments. The results also emphasise the importance of considering both parasitic and post-parasitic juvenile stages of mussels to maximise the positive effects of stressor mitigation.
  • 山田夏希, 森本淳子, 中村太士, 孫田敏
    日本緑化工学会誌 47 (1) 3 - 8 2021/08 [Refereed][Not invited]
  • Hyerin Kim, Yasushi Shoji, Takahiro Tsuge, Takahiro Kubo, Futoshi Nakamura
    People and Nature 3 (4) 861 - 871 2021/08 [Refereed]
     
    The initial purpose of our study was to understand preferences of stakeholders on green infrastructure for flood control using a discrete choice experiment. However, the results of our study included unexpected findings. According to the utility theory of economics, an inexpensive green infrastructure scenario should have been chosen under ceteris paribus conditions, but our results differed from this expectation. Inconsistent results like ours are often interpreted as indicating bias and/or questionnaire design issues. However, our results can be interpreted using relational values. We studied green infrastructure in a large-scale flood control basin in Naganuma, a town in the Hokkaido prefecture in Northern Japan. We conducted a discrete choice experiment with town residents as stakeholders of the green infrastructure. Through the examination of choice and membership parameters of our results, we interpreted that individual identity and place attachment, which are types of relational values, are taken into consideration in the choice situation of the discrete choice experiment. We also found that a notion of social responsibility, which is also a relational value, can help us to understand unexpected findings that cannot be interpreted in terms of economic theory alone. Relational values contribute to our interpretation of preferences related to managing ecosystem services with implications for green infrastructure, culturally significant wildlife, wildlife-related recreation and flood control. A free Plain Language Summary can be found within the Supporting Information of this article.
  • Hiroto Takinami, Nobuo Ishiyama, Takafumi Hino, Takahiro Kubo, Kanji Tomita, Muku Tsujino, Futoshi Nakamura
    Conservation Science and Practice 2578-4854 2021/07/13
  • Junko Morimoto, Mio Sugiura, Miho Morimoto, Futoshi Nakamura
    Frontiers in Forests and Global Change 4 2021/07/05 [Refereed]
     
    Questions have been raised about the application of conventional post-windthrow forest practices such as salvage logging, site preparation, and afforestation in response to the increase in wind disturbance caused by climate change. In particular, it is necessary to identify effective forest management practices that consider the pressure from deer browsing in forests in cold, snowy regions because the population of ungulates is expected to increase. The impacts of legacy destruction, i.e., the destruction of advance regeneration, microsites, and soil structure, caused by conventional post-windthrow practices have rarely been assessed separately from the impacts of subsequent deer browsing on forest regeneration or evaluated based on sufficiently long monitoring periods to assess vegetation succession. This lack of studies is one reason that alternative forest management practices to salvaging and planting have not been proposed. We conducted a field experiment at a large-scale windthrow site with a deer population to (1) assess the impact of legacy destruction and deer browsing on vegetation biomass and species composition after 15 years and (2) identify the effects of legacy retention. The study design allowed us to distinguish between and measure the impact of legacy destruction and that of subsequent deer browsing during a 15-year period. The results revealed the following: (1) Salvage logging and site preparation suppressed the development of biomass of shrub and tree layers in forested areas where harvest residues were piled up and shifted the plant communities in these areas to herbaceous plant communities. (2) Subsequent deer browsing suppressed the development of the biomass of shrub and tree layers throughout the forested site and shifted herbaceous communities to ruderal communities dominated by alien species; and 3. Compared with salvaging and planting, legacy retention enabled the windthrow sites to more quickly develop into a stand with characteristics similar to that of a mature, natural forest. Forest management practices that consider the presence of deer are necessary. We propose a policy shift from planting trees after salvaging to leaving downed trees to regenerate natural forests, unless there is concern about insect damage to the remaining forestry land in the vicinity.
  • Nobuo Ishiyama, Kazuki Miura, Takahiro Inoue, Masanao Sueyoshi, Futoshi Nakamura
    Conservation Biology 35 (3) 884 - 896 0888-8892 2021/06 [Refereed]
     
    Forest conversion is one of the greatest global threats to biodiversity, and land-use change and subsequent biodiversity declines sometimes occur over a variety of underlying geologies. However, how forest conversion and underlying geology interact to alter biodiversity is underappreciated, although spatial variability in geology is considered an integral part of sustaining ecosystems. We aimed to examine the effects of forest conversion to farmland, the underlying geology, and their interaction on the stream fishes’ diversity, evenness, and abundance in northeastern Japan. We disentangled complex pathways between abiotic and biotic factors with structural equation modeling. Species diversity of stream fishes was indirectly shaped by the interaction of land use and underlying geology. Diversity declined due to nutrient enrichment associated with farmlands, which was mainly the result of changes in evenness rather than by changes in species richness. This impact was strongest in streams with volcanic geology with coarse substrates probably because of the differential responses of abundant stream fishes to nutrient enrichment (i.e., dominance) and the high dependency of these fishes on large streambed materials during their life cycles. Our findings suggest that remediation of deforested or degraded forest landscapes would be more efficient if the interaction between land use and underlying geology was considered. For example, the negative impacts of farmland on evenness were larger in streams with volcanic geology than in other stream types, suggesting that riparian forest restoration along such streams would efficiently provide restoration benefits to stream fishes. Our results also suggest that land clearing around such streams should be avoided to conserve species evenness of stream fishes.
  • Tomoki Sakiyama, Junko Morimoto, Osamu Watanabe, Nobuyuki Watanabe, Futoshi Nakamura
    Global Ecology and Conservation 27 2021/06 [Refereed]
     
    Species distribution models can be used to predict favorable areas for population persistence under contemporary climate change. However, these predictions are often based on broad-scale environmental variables and lack consideration of local-scale environments. Small areas where species are protected from unfavorable regional conditions by using locally favorable conditions, which are called microrefugia, are therefore often overlooked in current approaches used to conserve biodiversity. Here, using a two-step approach, we explored the existence of microrefugia of a cold-adapted mammal, the Japanese pika (Ochotona hyperborea yesoensis). We first identified broad-scale factors related to Japanese pika distribution and distinguished broadly favorable and unfavorable areas. Then, we assessed whether environmental conditions favorable to Japanese pikas existed at the local scale in habitats where they were present in unfavorable areas by focusing on thermal, vegetative, and ground conditions. We found that the Japanese pika distribution was substantially restricted by the mean summer temperature, suggesting that lower elevation areas were unfavorable for persistence. However, subsequent local-scale measurements indicated that while the average summer temperature in the Japanese pika habitats was higher in unfavorable areas than in favorable areas, rock interstices prevented the average and acute heat stress from reaching the thresholds known to limit Japanese pika activity. Moreover, summer thermal conditions in rock interstices in unfavorable areas were more stable than those in favorable areas. Taken together, our results indicate that lower-elevation areas are predicted to be unfavorable due to the broad-scale climate, but microclimates that allow Japanese pikas to behaviorally thermoregulate exist at the local scale, thereby suggesting the existence of microrefugia. In addition, winter thermal conditions did not differ among all thermal indices between the areas, and unfavorable areas possessed more developed vegetation and fewer rock interstices. Our results highlight the importance of examining local habitat conditions and suggest that using only broad-scale assessments may risk overlooking areas with a high potential for conservation. In the case of Japanese pikas, cool and stable microclimates at lower elevations were found to possess high conservation value in terms of enhancing population persistence under climate change.
  • Munehiro Kitazawa, Yuichi Yamaura, Kazuhiro Kawamura, Masayuki Senzaki, Satoshi Yamanaka, Masashi Hanioka, Futoshi Nakamura
    Biodiversity and Conservation 30 (7) 2017 - 2032 0960-3115 2021/06 [Refereed]
     
    Abandoned farmland area has been expanding globally for decades. Studies showed that conservation value of abandoned farmland has differed among studies and regions, and thus is difficult to predict. However, predicting the effects of farmland abandonment on biodiversity remains vital to the development of appropriate conservation strategies. Here, we compared the species-, community-, and functional group-level habitat suitability of abandoned farmland for birds by comparison with active farmland (pasture, cropland, and rice paddy) and natural wetland on Hokkaido, Japan, over a study area of 400 km × 500 km. Results differed markedly between functional groups. The abundance and species richness of grassland species in abandoned farmland were higher than that in active farmland, and comparable to that in wetland. In contrast, abundance and richness of bare-ground species was highest in active farmland. For most species, interactive effects between climate variables and abandoned farmland were not significant, suggesting a consistent habitat suitability of abandoned farmland irrespective of varied climatic conditions. Our results suggest that abandoned farmland plays an important role as habitat for grassland and forest species at large scales; farmland abandonment provides a valuable alternative habitat for species whose primary habitats have been lost to agricultural expansion. Especially, abandoned farmland in warmer areas in Hokkaido would represent a potential mitigation to the negative effects of wetland loss. A functional group approach synthesizes varied species-level responses and allows for a comprehensive understanding of the habitat suitability of abandoned farmland. Adopting this approach will contribute to establishing appropriate conservation strategies.
  • Mirza A.T.M.Tanvir Rahman, Junjiro N. Negishi, Takumi Akasaka, Futoshi Nakamura
    Ecology and Evolution 11 (9) 4656 - 4669 2021/05 [Refereed]
     
    Hyporheic zone (HZ) locates below the riverbed providing habitat for macroinvertebrates from where the winged adult insects (i.e., hyporheic insects, HIs) emerge and bring out aquatic resources to the riparian zone. This study estimated mean daily flux as dry biomass (BM), carbon (C), and nitrogen (N) deriving from the dominant HI species Alloperla ishikariana (Plecoptera, Chloroperlidae) for a 4th-order gravel-bed river during the early-summer to summer periods. We hypothesized that HIs were an important contributor in total aquatic resources to the riparian zone. In 2017 and 2018, we set parallelly (May to August) and perpendicularly (June to October) oriented Malaise traps to catch the lateral and longitudinal directional dispersing winged adults of A. ishikariana, and other Ephemeroptera, Plecoptera, Trichoptera, and Diptera from the river and estimated the directional fluxes of them. We further split the directional fluxes as moving away or back to the channel (for lateral) and from down- to upstream or up- to downstream (for longitudinal). Alloperla ishikariana was similar to other Plecoptera species and differed clearly from Ephemeroptera and Trichoptera in directional characteristics of resources flux, suggesting that the extent and directions of HZ-derived resource transfer depend on taxon-specific flight behaviors of HIs. Contributions of A. ishikariana to the riparian zone in total aquatic C and N transfer seasonally varied and were lower in May (5%–6%) and August (2%–4%) and the highest in July (52%–70%). These conservative estimates largely increased (9% in May) after the supplementary inclusion of Diptera (Chironomidae and Tipulidae), part of which were considered HIs. We demonstrated that HZ could seasonally contribute a significant portion of aquatic resources to the riparian zone and highlighted the potential importance of HZ in nutrient balance in the river-riparian ecosystem.
  • Keita Kawajiri, Nobuo Ishiyama, Kazuki Miura, Akira Terui, Masanao Sueyoshi, Futoshi Nakamura
    Water (Switzerland) 13 (9) 2021/05/01 [Refereed]
     
    Freshwater mussels, Unionoida, are endangered across the globe due to recruitment failure. In the present study, with general linear mixed models, we investigated the relative effects of biotic (host fish density) and abiotic (water depth, fine sediment, water temperature, and water quality) factors on the recruitment of Margaritifera laevis in 10 streams of Hokkaido, northern Japan. We additionally examined the factors regulating the density of the host fish Oncorhynchus masou masou with general linear models. The proportion of juvenile mussels had a unimodal relationship with the host density, which was the most influential factor among the others examined. The positive relationship between mussel recruitment and host density can be attributed to an increased host fish infection rate. The negative correlation between mussel recruitment and host density at high fish densities may be due to reduced larval growth on host fish that are in poor physical condition. We also found that host fish density was negatively affected by nutrient enrichment. Our results suggest that mitigating water quality degradation to recover host fish density should be prioritized to improve mussel recruitment. Although stock enhancement is effective for increasing the salmon population density, excess stocking can further disturb mussel recruitment.
  • Lauretta Andrew Laneng, Futoshi Nakamura, Yasuyuki Tachiki, Charles S. Vairappan
    Landscape and Ecological Engineering 17 (2) 135 - 146 1860-1871 2021/04 [Refereed]
     
    The Innoprise-IKEA (INIKEA) Forest Rehabilitation Project in Kalabakan Forest Reserve, Sabah, was established to rehabilitate degraded forest affected by conventional logging and forest fires that occurred during an El-Nino event (1982–1983). The present study aimed to investigate the responses of ground-dwelling mammals and birds to the different rehabilitation practices in INIKEA: gap-cluster planting, line planting and liberation, where enrichment planting applied in both gap-cluster and line planting. A total of 74 camera traps were deployed at random locations across reforested INIKEA plots, including plots in control areas comprising naturally regenerated forest. A total of 6534 independent photographs of medium-to-large vertebrates from 7266 camera-trap nights representing 33 species from 14 families and 7 orders were obtained. Among the detected vertebrate species, 2 are listed as Critically endangered, 5 as Endangered, 8 as Vulnerable and 6 as Near threatened on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. Mousedeer was the most frequently photocaptured species, followed by muntjac, bearded pig, sambar deer, pig-tailed macaque and crested fireback. The present study demonstrates that the rehabilitation methods applied in INIKEA have aided forest recovery, providing habitat for the ground-dwelling mammals and birds in Sabah. General forest structure, species richness and species composition did not significantly differ between the areas subjected to rehabilitation treatment and the control area. The results suggest that the liberation method should be abandoned to ensure a variety of food resources for animal species. Provided major forest components remain after disturbance, disturbed forest areas should be left to undergo natural recovery.
  • Nanane Motosugi, Futoshi Nakamura, Souta Nakajima, Chihiro Takahata, Kazuhiro Kawamura, Junko Morimoto
    Landscape and Ecological Engineering 17 (2) 95 - 106 1860-1871 2021/04 [Refereed]
     
    There have been many earlier studies of the biodiversity and ecosystem services of abandoned farmlands, but studies of abandoned villages are limited, particularly in Asian countries. The drastic aging and depopulation of Japanese society will likely lead to increased village abandonment in the future. To properly manage abandoned villages and build a comprehensive land-use plan, we need to know how natural succession will proceed after the abandonment of local towns and villages. We investigated forest structures and compositions at the sites of abandoned mining villages and compared them with ambient undisturbed natural forests. The environmental factors that determine plant succession are the distance from ambient forests, land-use period, and years since abandonment. The results showed that the sizes of tall trees and species diversity of understory vegetation recovered to the level of the control sites approximately 50–60 years after village abandonment. However, the species compositions of tall trees and understory vegetation were fairly different from those of the control sites. The distance from ambient natural forest, which regulates the seed supply for abandoned sites; land-use periods, which are surrogates for the durations of anthropogenic disturbance; and times since abandonment are strong drivers of the recovery of forest species compositions.
  • Nanane Motosugi, Futoshi Nakamura, Souta Nakajima, Chihiro Takahata, Kazuhiro Kawamura, Junko Morimoto
    Landscape and Ecological Engineering 17 (2) 107  1860-1871 2021/04 [Refereed]
     
    In the original publication of the article, the following reference was not included and provided in this correction. Nakamura F, Ishiyama N, Yamanaka S, Higa M, Akasaka T, Kobayashi Y, Ono S, Fuke N, Kitazawa M, Morimoto J, Shoji Y (2020) Adaptation to climate change and conservation of biodiversity using green infrastructure. River Res Appl 36:921–933 The original article has been updated.
  • Kaiji Suzuki, Nobuo Ishiyama, Itsuro Koizumi, Futoshi Nakamura
    Water (Switzerland) 13 (7) 2021/04 [Refereed]
     
    Clarifying the combined effects of water temperature and other environmental factors on the species distributions of cold-water fishes is the first step toward obtaining a better understanding of the complex impacts of climate warming on these species. In the present study, we examined the abundance and occurrence of the fluvial sculpin, Cottus nozawae, in response to water temperature along environmental gradients in northern Japan. The abundance survey was conducted in the Sorachi River catchment with two-pass electrofishing with a backpack electrofisher. For the occurrence survey, we carried out one-pass electrofishing in the Sorachi, Chitose, and Tokachi River catchments. Fish sampling was conducted once from July to August 2018 in the Sorachi River catchment, from May to June 2011 in the Chitose River catchment, and from July to September 2012 in the Tokachi River catchment. Generalized linear mixed models (GLMMs) and generalized linear models (GLMs) were used for the abundance and occurrence analyses, respectively. We found that the mean summer water temperature was the most influential factor on the distribution of C. nozawae; the abundance and occurrence were both negatively affected by increased water temperatures. In the occurrence model, occurrence probabilities of 0.9 and 0.5 for C. nozawae corresponded to mean summer temperatures of 12.0 and 16.1 °C, respectively. Furthermore, we identified a combined effect of water temperature and current velocity on the abundance of C. nozawae. The increased mean summer water temperature had a stronger negative effect on C. nozawae abundance under gentle flow conditions. While the precise mechanisms of this combined effect could not be determined in this study, stressors associated with low current velocities may increase their vulnerability to higher water temperatures. Our findings indicate that flow disturbances caused by human activities such as excessive water abstraction may exacerbate the negative impacts of climate warming on populations of C. nozawae in the future.
  • Yu NAGATA, Junko MORIMOTO, Yoshifumi SAKURAI, Koji KIMURA, Futoshi NAKAMURA
    Journal of the Japanese Society of Revegetation Technology 46 (3) 308 - 315 0916-7439 2021/02/28
  • Futoshi NAKAMURA, Yukihiro SHIMATANI, Kazuaki OHTSUKI, Hideaki SEKINE, Kentaro TAKI, Jun NISHIHIRO, Morihiro HARADA
    Ecology and Civil Engineering 1344-3755 2021
  • Junko Morimoto, Masahiro Aiba, Flavio Furukawa, Yoshio Mishima, Nobuhiko Yoshimura, Sridhara Nayak, Tetsuya Takemi, Haga Chihiro, Takanori Matsui, Futoshi Nakamura
    Forest Ecology and Management 479 0378-1127 2021/01/01 [Refereed]
     
    Under future climate regimes, the risk of typhoons accompanied by heavy rains is expected to increase. Although the risk of disturbance to forest stands by strong winds has long been of interest, we have little knowledge of how the process is mediated by storms and precipitation. Using machine learning, we assess the disturbance risk to cool-temperate forests by typhoons that landed in northern Japan in late August 2016 to determine the features of damage caused by typhoons accompanied by heavy precipitation, discuss how the process is mediated by precipitation as inferred from the modelling results, and delineate the effective solutions for forest management to decrease the future risk in silviculture. In the results, we confirmed two types of behaviours in the model: one represents the same process as that of forest disturbance by strong wind, which has been widely studied, and another represents a unique process mediated by storms and precipitation that has not been previously investigated. Specifically, the ridges that received strong wind from the front side had the highest risk of disturbance. Precipitation increased the probability of disturbance in forest stands, and its effect was dependent on the dominant species composition. Our hypothesis regarding treefall mediated by storms and precipitation is that rainwater flows into the gaps around the tree root systems during sway and the introduction of rainwater below the root-soil plate decreases the root anchorage. The species-specific vulnerability to rainfall may depend on the volume of lateral roots. Modelling the disturbance risk helped us to examine the kinds of factors that were related to exposure and vulnerability that should be managed to effectively decrease the risk of disturbance by typhoons during future uncontrollable hazards. It is recommended to avoid silviculture on the ridges of plateaus considering the high risk estimated in this area. In addition, species with dense lateral roots would be suitable for planting because they may have high resistance to typhoons with heavy precipitation.
  • Tomoki Sakiyama, Junko Morimoto, Jun Matsubayashi, Yasuto Furukawa, Mami Kondo, Hifumi Tsuruga, Tsutomu Mano, Futoshi Nakamura
    Landscape and Ecological Engineering 1860-1871 2021 [Refereed]
     
    Investigating factors underlying human-wildlife conflicts in agricultural landscapes is important for both preventing crop damage and wildlife conservation. Although environments surrounding crop fields are considered causal factors, incorporating individual aspects of animals, such as demographic and physical characteristics, into the investigation may aid the prediction of how nuisance control affects wildlife population structures. Here, we assessed the relationship of corn consumption by Hokkaido brown bears (Ursus arctos) with both demographic (sex and age) and physical (body size) characteristics and environmental factors (human presence and crop accessibility). We estimated the proportion of corn in the lifespan diet for both female (n = 61) and male (n = 62) bears using carbon and nitrogen stable isotope analyses. Then, we analyzed the factors correlated with corn consumption using a generalized linear model. Female and male bears consumed corn from 1.3 to 30.9% and 1.3 to 42.0% of their lifespan diet, respectively. Corn consumption by female bears was not correlated with any explanatory variables, whereas that of male bears was positively correlated with their body size and crop accessibility but negatively correlated with human presence. Large male bears were more likely to have consumed more corn than small male bears, but the selective harvest of large bears may cause dwarfism of their overall population, impacting the local population dynamics. To reduce agricultural damage and population structure alteration of brown bears, the opportunity for them to learn to eat crops must be eliminated through border management between forests and agricultural fields and the relocation of agricultural fields when possible.
  • Kazuhiro Kawamura, Yuichi Yamaura, Masashi Soga, Rebecca Spake, Futoshi Nakamura
    Journal of Forest Research 26 (3) 237 - 246 1341-6979 2021 [Refereed]
     
    Natural forests were increasingly replaced by plantations globally. While plantations support less biodiversity compared to natural forests, they can serve as an important habitat for forest-dependent species. Understanding the key drivers of the habitat function of plantations is necessary to reconcile both forestry and biodiversity. Planted tree species is one of the important factors determining biodiversity of plantations. Here, we systematically collected studies comparing the biodiversity between conifer plantations and natural forests, and conducted meta-analyses to quantify the effects of planted tree family/species (cypress family: Japanese cedar Cryptomeria japonica, Hinoki cypress Chamaecyparis obtuse; pine family: Japanese larch Larix kaempferi, Japanese red pine Pinus densiflora, Todo fir Abies sachalinensis) on abundance and species richness of a wide range of taxa (all taxa, vertebrates, birds, invertebrates, terrestrial arthropods, plants, and understorey plants) in plantations in Japan. Abundance and species richness in plantations relative to natural forests differed among planted tree family/species. In plantations of pine family (mainly larch), abundance or richness did not significantly differ from those in natural forests for many taxa, suggesting the important role as habitats. By contrast, in cypress family (mainly cedar), abundance or richness was significantly lower than in natural forests for all analysis groups except understorey abundance. These results indicate that the habitat function of plantations and its management should be considered for each planted tree species, separately. Nevertheless, since our literature review identifies some research gaps, e.g. studies on vertebrates in western Japan were scarce, more comprehensive research efforts should be made in the future.
  • Shigeya Nagayama, Nobuo Ishiyama, Taro Seno, Hideyuki Kawai, Yoichi Kawaguchi, Daisuke Nakano, Futoshi Nakamura
    Water (Switzerland) 12 (12) 2020/12 [Refereed]
     
    Despite a steep increase in dam removal projects, there are few studies on the biophysical responses to dam removal. In this study, we evaluated the short-term (1.5 years) and long-term (5.5 years) effects of partial check dam removal on fish assemblages and their habitats. First, the habitat preferences of fish were examined at a channel unit scale: pools, rapids, and side channels satisfied the seasonal habitat requirements of the fish assemblages. Partial check dam removal increased the abundance of these habitats and diversified the habitat structures owing to the sediment release from the dam; in contrast, the bedrock distinctly decreased 1.5 years after dam removal. However, 5.5 years after dam removal, the bedrock proportion increased, and the habitat structures were simplified again owing to the re-transportation of sediments. Similar temporal changes were also determined through a reach-scale analysis with a change in the bed materials. Anadromous Oncorhynchus masou began to spawn and recolonize in the upstream section of the dam after the dam removal, causing similar assemblage compositions between the downstream and upstream sections. The abundance of Salvelinus malma and Noemacheilus barbatulus toni in the upstream reaches decreased over time after the dam removal. The temporal changes in the biophysical responses suggest that long-term monitoring is indispensable for the reliable evaluation of dam removal effects.
  • Futoshi Nakamura, Yasuharu Watanabe, Junjiro Negishi, Takumi Akasaka, Yuki Yabuhara, Akira Terui, Satoshi Yamanaka, Miwa Konno
    Ecological Engineering 157 0925-8574 2020/10/01 [Refereed]
     
    A braided gravel-bed river provides essential habitats for various plants and animals. However, human regulation of rivers, such as dams, channelization, and other engineering works, alter flow and sediment regimes, which generally cause the degradation of river and riparian ecosystems. One of the prominent changes prevailing in Japanese rivers is forest expansion over gravel bars, and many native plants and animals that depend on gravel-bar habitat are now endangered. The Satsunai River is typical of rivers experiencing forest expansion, so the Japanese government launched a restoration project in 2012 to partially restore its riparian ecosystems. This is a large-scale experiment developed jointly by an interdisciplinary science team and river managers, who conduct monitoring and evaluation under an adaptive management scheme. The main measure to restore gravel bed habitat was an artificial flood regime, releasing a maximum water volume of 120 m3/s, which was a 2-year return period flood before dam construction. A unique feature of the project is that we considered the role of high-magnitude floods with recurrence intervals greater than 20 years after dam construction. We hypothesize that the artificial floods can be timed seasonally to create sites for regeneration and nesting of riparian species, and the high-magnitude floods contribute to maintaining a shifting mosaic structure of floodplain forest and unvegetated gravel-bar patches. We also used critical non-dimensional shear stress analysis to define “flood-disturbance areas” that can be disturbed under the artificial flow regime created by a dam. Artificial floods have been initiated once a year since 2012 at the end of June, synchronized with the seed dispersal period of Salix arbutifolia, which is endangered and a high conservation priority in the project. Thus far, the idea of setting floodplain-disturbance areas and the strategy of using both artificial and high-magnitude floods to restore a shifting mosaic of floodplain habitat patches is appropriate, as we found successful regeneration of S. arbutifolia and an exponential decay curve of the age distribution of floodplain forest patches. However, the sediment regime regulated by the dam was not addressed in this research, so future monitoring should track changes in river morphology associated with reduced sediment supply caused by the dam.
  • Taihei Yamada, Itsuro Koizumi, Hirokazu Urabe, Futoshi Nakamura
    ZOOLOGICAL SCIENCE 37 (5) 429 - 433 0289-0003 2020/10 [Refereed]
     
    Condition-specific competition is a phenomenon by which inter-specific competitive dominance changes as a result of environment, and is an important factor determining species distribution. Congeneric charrs in Hokkaido, Japan, provide one of the best examples of condition- specific competition: Dolly Varden, Salvelinus malma, often dominate in cold streams (6-8 degrees C), whereas white-spotted charr, Salvelinus leucomaenis, dominate in warmer streams (> 10 degrees C). While past laboratory and field experiments have demonstrated the great advantage of white-spotted charr at higher water temperatures, the advantages of Dolly Varden at lower temperature have not always been clear. Here, we examined the effect of water temperature (6 degrees C vs. 12 degrees C) on the swimming ability of the two sympatric charrs using a stamina tunnel. At 6 degrees C, the swimming ability of Dolly Varden was greater than that of white-spotted charr, but no difference was observed at 12 degrees C. These results suggest that the temperature-mediated swimming ability differs between these species, which may explain the coexistence of the closely related species within heterogeneous habitats via condition- specific competition.
  • Souta Nakajima, Shun K. Hirota, Ayumi Matsuo, Yoshihisa Suyama, Futoshi Nakamura
    Water (Switzerland) 12 (9) 2020/09 [Refereed]
     
    White-spotted charr (Salvelinus leucomaenis leucomaenis) is an anadromous fish that has been severely harmed by human land-use development, particularly through habitat fragmentation. However, the anthropogenic impacts on populations of this species have not been evaluated, except those on small dammed-off populations. Using multiplexed ISSR genotyping by sequencing, we investigated the genetic structure of white-spotted charr in four tributaries in the upper section of the Kanayama Dam in the Sorachi River, Hokkaido Island, Japan. There were no distinct genetic structures (FST = 0.014), probably because some active individuals migrate frequently among tributaries. By model-flexible demographic simulation, historical changes in the effective population size were inferred. The result indicates that the population size has decreased since the end of the last glacial period, with three major population decline events, including recent declines that were probably associated with recent human activities. Nevertheless, populations in the watershed upstream of the Kanayama Dam are still expected to be at low risk of immediate extinction, owing to the large watershed size and the limited number of small check dams. An effective conservation measure for sustaining the white-spotted charr population is to maintain high connectivity between tributaries, such as by providing fishways in check dams during construction.
  • Yoshiko Kobayashi, Motoki Higa, Kan Higashiyama, Futoshi Nakamura
    PLoS ONE 15 (7 July) 2020/07 [Refereed]
     
    The extraordinary population growth of the 20th century will subside in the 21st century, followed by depopulation, constituting the first population decline phase in human history in Japan and other developed countries. The drivers of land-use change during the population decline phase are expected to differ from those of the population growth phase; however, research on land-use drivers during the decline phase is limited. Identifying these drivers is necessary to develop effective management plans for biodiversity and ecosystem services in the decline phase. First, we calculated the probability of farmland abandonment in Hokkaido, a Japanese food production area, from 1973-2009 and divided the period into the population growth phase (1978-1997) and the decline phase (1997-2009). We examined various geographical and social factors that were assumed to alter the land use during these two phases. Geographical and social conditions are key factors in determining the probability of farmland abandonment, but their influences varied between the two phases. The farmlands located on geographically uncultivable sites, such as marginal, underproductive, narrow, and steep land, were abandoned during these phases; however, social conditions, such as the distance from densely inhabited districts (DIDs) and the population, exerted opposite effects during these two phases. Farmland abandonment occurred near DIDs (i.e., urban areas) during the population growth phase, whereas farmland abandonment occurred far from DIDs and sparsely populated farmlands during the decline phase. Farmland abandonment was strongly affected by government policy during the population growth phase, but the policy weakened during the decline phase, which triggered farmland abandonment throughout Hokkaido. The geographical and social drivers found in the present study may provide new insights for other developed countries experiencing depopulation problems.
  • Wataru Hotta, Junko Morimoto, Takahiro Inoue, Satoshi N. Suzuki, Toshihiro Umebayashi, Toshiaki Owari, Hideaki Shibata, Satoshi Ishibashi, Toshihiko Hara, Futoshi Nakamura
    Forest Ecology and Management 468 0378-1127 2020/04 [Refereed][Not invited]
     
    To mitigate the negative effects of climate change, it is necessary to conserve carbon stocks in forests. Typhoons fell many standing trees and generate a substantial amount of coarse woody debris (CWD). In boreal forests, CWD contributes to maintaining carbon stocks for a long time after a disturbance because the decomposition rate of CWD is relatively low. We know that salvage logging after a disturbance tremendously decreases the forest carbon stock over the short term after logging but know little about its long-term effects. We targeted a catastrophic windthrow caused by a super typhoon in 1954 in boreal forests in northern Japan and estimated the long-term effects of salvage logging after the windthrow on the above- and belowground carbon stocks by comparing old-growth forests with low damage from the super typhoon in 1954 or any subsequent typhoons (OG), forests damaged by the typhoon with remaining CWD (i.e., windthrow, WT), and forests damaged by the typhoon followed by salvage logging (WT + SL). The CWD carbon stock of decay class 5 (i.e., the most decayed CWD) in WT was significantly larger than that in OG and WT + SL, suggesting that the CWD in decay class 5 in WT had been generated by the typhoon 64 years ago, and the negative effect of salvage logging on the carbon stock still remains apparent in the CWD carbon stock of decay class 5. The carbon stock of the organic (O) layer in WT was larger than that in WT + SL, probably because of three factors: (1) the slower decomposition rate of fallen leaves and twigs of conifers than broadleaves, as conifer litter is abundant in WT; (2) greater carbon transition from the CWD to the O layer in WT; and (3) the occurrence of a lower decomposition rate in the O layer in WT. However, the total carbon stock in WT + SL has almost recovered to the level of that in WT within the last 64 years. The carbon stocks of broadleaves that grew rapidly after the disturbance and the newly accumulated dead trees generated throughout the stand developmental process might contribute to the recovery of carbon stock in WT + SL. These results indicate that salvage logging affects the allocation of carbon in the forest even after 64 years after a catastrophic windthrow, although there was no large difference in total carbon stock.
  • Nobuo Ishiyama, Kazuki Miura, Satoshi Yamanaka, Junjiro N. Negishi, Futoshi Nakamura
    Journal of Applied Ecology 57 (3) 548 - 558 0021-8901 2020/03/01 [Refereed]
     
    Habitat fragmentation, which involves habitat size reduction and isolation, is a major cause of biodiversity decline. However, interest in small isolated habitats has increased among ecosystem managers because these fragments can serve as remnant refuges for unique and/or endangered species in human-altered landscapes. In a fragmented floodplain of northern Japan, we demonstrate how habitat fragmentation and habitat quality shape the refuges for a unique endangered minnow Rhynchocypris percnurus sachalinensis from biological invasions. We focused on two invasive minnows, topmouth gudgeon Pseudorasbora parva and rosy bitterling Rhodeus ocellatus ocellatus, which are the dominant invasive species. By using a graph theoretical approach and structural equation modelling, we elucidated the relationships among habitat fragmentation, habitat quality and the abundance of invasive minnows with the endangered swamp minnow. We found that the invasion of topmouth gudgeon, which has a high mobility and environmental tolerance, negatively affected swamp minnow populations. The invasive species may outcompete the native species in their overlapping trophic niche. Analyses indicated that habitat fragmentation (decreasing habitat size and connectivity) indirectly and positively affected the population abundance of swamp minnow by reducing the potential for invasion by topmouth gudgeon. We further found an interaction between the indirect effects of habitat fragmentation and local habitat quality: the indirect effects became more apparent in the relatively deeper habitats that were of better quality for natives. This result was likely attributed to the strong control effect of the abiotic stressor. Interspecific competition between the two minnows would be masked in shallow ponds because the native populations are primarily restricted by the abiotic factor, and its abundance is inherently limited regardless of pressure by invaders. Synthesis and applications. In fragmented landscapes, evenly conserving all small fragments within a limited budget is difficult. The change in importance of small isolated ponds across a pond-depth gradient suggests that conservation priorities for small fragments should be established by considering local habitat quality. Our findings do not justify habitat fragmentation but suggest that both landscape-scale and local-scale perspectives synergistically aid in the management of biological invasions in modified habitat networks.
  • 堀田亘, 森本淳子, 芳賀智宏, 松井孝典, 鈴木智之, 尾張敏章, 中村太士
    日本生態学会大会講演要旨(Web) 67th 2020/03 [Not refereed][Not invited]
  • Ai Hojo, Kentaro Takagi, Ram Avtar, Takeo Tadono, Futoshi Nakamura
    Remote Sensing 12 (3) 2020/02/01 [Refereed]
     
    In this study, we compared the accuracies of above-ground biomass (AGB) estimated by integrating ALOS (Advanced Land Observing Satellite) PALSAR (Phased-Array-Type L-Band Synthetic Aperture Radar) data and TanDEM-X-derived forest heights (TDX heights) at four scales from 1/4 to 25 ha in a hemi-boreal forest in Japan. The TDX heights developed in this study included nine canopy height models (CHMs) and three model-based forest heights (ModelHs); the nine CHMs were derived from the three digital surface models (DSMs) of (I) TDX 12 m DEM (digital elevation model) product, (II) TDX 90 m DEM product and (III) TDX 5 m DSM, which we developed from two TDX-TSX (TerraSAR-X) image pairs for reference, and the three digital terrain models (DTMs) of (i) an airborne Light Detection and Ranging (LiDAR)-based DTM (LiDAR DTM), (ii) a topography-based DTM and (iii) the Shuttle Radar Topography Mission (SRTM) DEM; the three ModelHs were developed from the two TDX-TSX image pairs used in (III) and the three DTMs (i to iii) with the Sinc inversion model. In total, 12 AGB estimation models were developed for comparison. In this study, we included the C-band SRTM DEM as one of the DTMs. According to Walker et al. (2007), the SRTM DEM serves as a DTM for most of the Earth's surface, except for the areas with extensive tree and/or shrub coverage, e.g., the boreal and Amazon regions. As our test site is located in a hemi-boreal zone with medium forest cover, we tested the ability of the SRTM DEM to serve as a DTM in our test site. This study especially aimed to analyze the capability of the two TDX DEM products (I and II) to estimate AGB in practice in the hemi-boreal region, and to examine how the different forest height creation methods (the simple DSM and DTM subtraction for the nine CHMs and the Sinc inversion model-based approach for the three ModelHs) and the different spatial resolutions of the three DSMs and three DTMs affected the AGB estimation results. We also conducted the slope-class analysis to see how the varying slopes influenced the AGB estimation accuracies. The results show that the combined use of the PALSAR data and the CHM derived from (I) TDX 12 m DEM and (i) LiDAR DTM achieved the highest AGB estimation accuracies across the scales (R2 ranged from 0.82 to 0.97), but the CHMs derived from (I) TDX 12 m DEM and another two DTMs, (ii) and (iii), showed low R2 values at any scales. In contrast, the two CHMs derived from (II) TDX 90 m DEM and both (i) LiDAR DTM and (iii) SRTM DEM showed high R2 values > 0.87 and 0.78, respectively, at the scales > 9.0 ha, but they yielded much lower R2 values at smaller scales. The three ModelHs gave the lowest R2 values across the scales (R2 ranged from 0.39 to 0.60). Analyzed by slope class at the 1.0 ha scale, however, all the 12 AGB estimation models yielded high R2 values > 0.66 at the lowest slope class (0° to 9.9°), including the three ModelHs (R2 ranged between 0.68 to 0.69). The two CHMs derived from (II) TDX 90 m DEM and both (i) LiDAR DTM and (iii) SRTM DEM showed R2 values of 0.80 and 0.71, respectively, at the lowest slope class, while the CHM derived from (I) TDX 12 m DEM and (i) LiDAR DTM showed high R2 values across the slope classes (R2 > 0.82). The results show that (I) TDX 12 m DEM had a high capability to estimate AGB, with a high accuracy across the scales and the slope classes in the form of CHM, but the use of (i) LiDAR DTM was required. On the other hand, (II) TDX 90 m DEM was able to achieve high AGB estimation accuracies not only with (i) LiDAR DTM, but also with (iii) SRTM DEM in the form of CHM, but it was limited to large scales > 9.0 ha; however, all the models developed in this study have the possibility to achieve higher AGB estimation accuracies at the 1.0 ha scale in flat terrains with slope < 10°. The analysis showed the strengths and limitations of each model, and it also indicates that the data creation methods, the spatial resolutions of datasets and topographic features affects the effective spatial scales for AGB mapping, and the optimal combinations of these features should be chosen to obtain high AGB estimation accuracies.
  • The role of ditches in agricultural landscapes in conserving the diversity of wetland plants.
    豊島楽子, 森本淳子, 中村太士
    日本緑化工学会誌 2020 [Refereed][Not invited]
  • KAWAJIRI Keita, SUEYOSHI Masanao, ISHIYAMA Nobuo, OHTA Tamihisa, FUKUZAWA Karibu, NAKAMURA Futoshi
    Ecology and Civil Engineering 応用生態工学会 22 (2) 133 - 148 1344-3755 2020 [Refereed][Not invited]
     

    In the northern snowy region of Japan, chloride deicers, which are mainly composed of NaCl, are widely used to prevent road surfaces from freezing. Large amounts of the scattered chlorides accumulate at snow disposal sites and flow into streams with snowmelt runoff. Here, we studied how the snowmelt runoff affects stream water quality and organisms in Sapporo, Japan. We measured water quality at the outlet of snow disposal and adjacent stream, both at upstream (control) and downstream (impact) reaches of the outlet, for several sites. We also collected benthic algae and macroinvertebrates at both stream reaches. The results showed that the concentrations of Na and Cl in runoff water were 2-9 times higher than those in stream water during the early snowmelt period (March). Additionally, the concentrations of both ions in the stream water were higher in impact reaches than in control reaches, although the differences were relatively low (average ± S.D.=1.56 ±1.27 mg L-1 for Na and 3.05 ± 2.74 mg L-1 for Cl). For instream organisms, abundance of Trichoptera, total abundance of EPT (Ephemeroptera, Plecoptera, Trichoptera) and relative abundance of EPT to total macroinvertebrates were lower in impact reaches than in control reaches and decreased over the snowmelt period. To conserve stream ecosystems, we need to mitigate the impacts on stream water quality and organisms by preventing direct inflow of snowmelt runoff water.

  • Yamanaka S, Ishiyama N, Senzaki M, Morimoto J, Kitazawa M, Fuke N, Nakamura F
    Ecological Engineering 142 105617  0925-8574 2020 [Refereed][Not invited]
     
    In the era of global climate change, the risk of large-scale flood disasters has been increasing. Green infrastructure has gained increasing attention as one of the strategies for adaptation to mega-floods because it can concurrently enhance regional biodiversity and ecosystem services. Previous studies have assessed the efficacy of flood-control infrastructure in protecting biodiversity in urban areas. However, whether such infrastructure enhances biodiversity in other environments remains largely unknown. In this study, we assessed the function of flood-control basins constructed for flood risk management as summer habitat for wetland species in agricultural landscapes. We compared the species assemblages of four different taxa (fishes, aquatic insects, birds, and plants) among four water body types (flood-control basins, channelized watercourses, drainage pumping stations, and remnant ponds). We found that the flood-control basins had comparable or higher species richness and abundance of most taxa than the other water body types. We also found that the species compositions in the flood-control basins were characterized by pioneer species, which prefer shallow water or can adapt to fluctuations in water levels (e.g., herbivorous insects, shorebirds, and hygrophytes). These findings suggest that flood-control basins can provide summer habitat for wetland species, especially for species that inhabit environments with hydrological variation, and utilizing flood-control basins as green infrastructure is a reasonable option for conserving regional biodiversity in agricultural landscapes.
  • Nakamura, F, Ishiyama, N, Yamanaka, S, Higa, M, Akasaka, T, Kobayashi, Y, Ono, S, Fuke, N, Kitazawa, M, Morimoto, J, Shoji, Y
    River Research and Applications (forthcoming) (6) 921 - 933 1535-1459 2019/11 [Refereed][Not invited]
     
    In recent years, we have experienced mega-flood disasters in Japan due to climate change. In the last century, we have been building disaster prevention infrastructure (artificial levees and dams, referred to as “grey infrastructure”) to protect human lives and assets from floods, but these hard protective measures will not function against mega-floods. Moreover, in a drastically depopulating society such as that in Japan, farmland abandonment prevails, and it will be more difficult to maintain grey infrastructure with a limited tax income. In this study, we propose the introduction of green infrastructure (GI) as an adaptation strategy for climate change. If we can use abandoned farmlands as GI, they may function to reduce disaster risks and provide habitats for various organisms that are adapted to wetland environments. First, we present a conceptual framework for disaster prevention using a hybrid of GI and conventional grey infrastructure. In this combination, the fundamental GI, composed of forests and wetlands in the catchment (GI-1) and additional multilevel GIs such as flood control basins that function when floodwater exceeds the planning level (GI-2) are introduced. We evaluated the flood attenuation function (GI-1) of the Kushiro Wetland using a hydrological model and developed a methodology for selecting suitable locations of GI-2, considering flood risk, biodiversity and the distribution of abandoned farmlands, which represent social and economic costs. The results indicated that the Kushiro Wetland acts as a large natural reservoir that attenuates the hydrological peak discharge during floods and suitable locations for introducing GI-2 are concentrated in floodplain areas developing in the downstream reaches of large rivers. Finally, we discussed the network structure of GI-1 as a hub and GI-2 as a dispersal site for conservation of the Red-crowned Crane, one of the symbolic species of Japan.
  • Kazuki Miura, Nobuo Ishiyama, Keita Kawajiri, Keisuke Atsumi, Michikusa Tachibana, Yu Nagasaka, Yoshiyasu Machida, Gao Yiyang, Junjiro N. Negishi, Itsuro Koizumi, Futoshi Nakamura
    Ecological Research 34 (5) 667 - 677 0912-3814 2019/09/01 [Refereed]
     
    Species identification is a fundamental process for ecological studies and conservation practices, and simple nonlethal identification criteria are important for endangered species. This study developed species identification criteria for two endangered freshwater pearl mussels (Margaritifera laevis and Margaritifera togakushiensis) based on linear discriminant functions (LDFs) that were established considering intraspecific regional morphological differences from sites at Hokkaido, northern Japan. We collected a total of 1,110 mussels from 52 rivers across 32 watersheds in two geographical regions (east and west). Shell morphologies (length, height, and width) of the collected mussels were measured, followed by species identification with gel electrophoresis banding patterns of 16S rRNA polymerase chain reaction products. LDFs were constructed for two size classes (≥40 mm and < 40 mm) using forward stepwise procedures to determine key morphological differences between the two species and consideration of whether regional morphological differences improved identification accuracies. The LDFs revealed that the morphologies of the two species were clearly distinguished by the relationship between height and length for both size classes. Region-specific LDFs produced better identification accuracies. Regardless of region, the maximum length of M. laevis exceeded 100 mm, whereas all M. togakushiensis were < 100 mm in length. Identification accuracies of the established LDFs were high for each of the five length classes (0–20 mm, 20–40 mm, 40–60 mm, 60–80 mm, and 80–100 mm) with 85–96% (mean: 92%) accuracy in the east and 67–96% (mean: 80%) in the west. These criteria for species identification will progress future ecological studies and conservation practices for freshwater mussels.
  • Keita Ooue, Nobuo Ishiyama, Masaki Ichimura, Futoshi Nakamura
    Biological Invasions 21 (8) 2639 - 2652 1387-3547 2019/08/15 [Refereed]
     
    Floodplain ecosystems that are characterized by high habitat heterogeneity and hydrological connectivity are considered hotspots for freshwater biodiversity. However, these biodiversity-rich areas have been seriously threatened by biological invasions. The signal crayfish (Pacifastacus leniusculus) is listed as 100 of the world’s worst invasive species, and is a major threat to freshwater biodiversity and ecosystem functioning. Here, we examined environmental factors relating to the invasion success of signal crayfish and their morphological responses in floodplain waterbodies. Classification and regression tree analyses showed that most of the influential factors differed between tributary and lake populations. In floodplain tributaries, the occurrence of crayfish was positively related with water temperature and abundance of leaf cover, while crayfish abundance was highest where large-wood was abundant. In floodplain lakes, crayfish were absent at oxygen-poor sites, and abundant at sites with high connectivity to a main channel. These results indicate that conservation practitioners should consider different environmental factors in accordance with strategies for invasive species management (i.e., offensive or defensive management). Furthermore, we demonstrated morphological differences between tributary and lake populations, with tributary crayfish having wider chelae. These morphological differences might have resulted from the physical differences between the two types of waterbodies, facilitating the rapid invasion of signal crayfish to floodplain waterbodies. Our study showed that invasion-risk assessments should consider both environmental factors and morphological responses to new environments to understand invasion ecology and to form effective conservation plans and to prioritize management actions.
  • Virginia Ruiz-Villanueva, Bruno Mazzorana, Ernest Bladé, Livia Bürkli, Pablo Iribarren-Anacona, Luca Mao, Futoshi Nakamura, Diego Ravazzolo, Dieter Rickenmann, Marcos Sanz-Ramos, Markus Stoffel, Ellen Wohl
    Earth Surface Processes and Landforms 44 (9) 1694 - 1709 0197-9337 2019/07 [Refereed]
     
    Inorganic sediment is not the only solid-fraction component of river flows; flows may also carry significant amounts of large organic material (i.e. large wood), but the characteristics of these wood-laden flows (WLFs) are not well understood yet. With the aim to shed light on these relatively unexamined phenomena, we collected home videos showing natural flows with wood as the main solid component. Analyses of these videos as well as the watersheds and streams where the videos were recorded allowed us to define for the first time WLFs, describe the main characteristics of these flows and broaden the definition of wood transport regimes (adding a new regime called here hypercongested wood transport). According to our results, WLFs may occur repeatedly, in a large range of catchment sizes, generally in steep, highly confined single thread channels in mountain areas. WLFs are typically highly unsteady and the log motion is non-uniform, as described for other inorganic sediment-laden flows (e.g. debris flows). The conceptual integration of wood into our understanding of flow phenomena is illustrated by a novel classification defining the transition from clear water to hypercongested, wood and sediment-laden flows, according to the composition of the mixture (sediment, wood, and water). We define the relevant metrics for the quantification and modelling of WLFs, including an exhaustive discussion of different modelling approaches (i.e. Voellmy, Bingham and Manning) and provide a first attempt to simulate WLFs. We draw attention to WLF phenomena to encourage further field, theoretical, and experimental investigations that may contribute to a better understanding of flows in river basins, leading to more accurate predictions, and better hazard mitigation and management strategies. © 2019 John Wiley & Sons, Ltd.
  • Kazuhiro Kawamura, Yuichi Yamaura, Masayuki Senzaki, Mutsuyuki Ueta, Futoshi Nakamura
    Ecology and Evolution 9 (13) 7549 - 7561 2019/07 [Refereed]
     
    Aim: Many studies have examined large-scale distributions of various taxa and their drivers, emphasizing the importance of climate, topography, and land use. Most studies have dealt with distributions over a single season or annually without considering seasonality. However, animal distributions and their drivers can differ among seasons because many animals migrate to suitable climates and areas with abundant prey resources. We aim to clarify seasonality in bird distributions and their drivers. Location: Japan. Methods: We examined the effects of climate (annual mean temperature, snow depth), topography (elevation), and land use (extent of surrounding habitat) on bird species richness, in the breeding and wintering seasons separately, using nationwide data (254 forest and 43 grassland sites, respectively). We separately analyzed the species richness of all species, residents, short-, and long-distance migrants in forests and grasslands. Results: In the breeding season, the annual mean temperature negatively affected all groups (except for forest and grassland residents), and the extent of surrounding habitat positively affected many groups. By contrast, in the wintering season, temperature positively affected all groups (except for forest residents), and the extent of surrounding habitat positively affected only grassland long-distance migrants. In both seasons, the species richness of forest and grassland residents was high in regions of moderate and high temperature, respectively. Moreover, snow depth negatively affected all forest groups in the wintering season. Mapping expected species richness suggested that regions with different climates served as habitats for different groups during different seasons. Main conclusions: All regions were important bird habitats depending on the season, reflecting the contrasting effects of temperature across seasons. In the breeding season, surrounding land use was also an important driver. To understand the seasonal role that each region and environment plays in maintaining species/communities, a large-scale study considering both environmental seasonality and species distribution is needed.
  • Recovery of wetland vegetation in the Maizuru flood-retarding basin in the Chitose River
    Akito Kuroyanagi, Junko Morimoto, Yuichiro Shida, Naohisa Shinsho, Kazuo Yabe, Futoshi Nakamura
    日本緑化工学会誌 45 2019/07 [Refereed][Not invited]
  • Ohsawa Takafumi, Furuta Naoya, Nakamura Futoshi, Kadoya Taku, Nakashizuka Tohru
    Japanese Journal of Conservation Ecology 一般社団法人 日本生態学会 24 (1) 95 - 107 1342-4327 2019/05/30 [Refereed][Not invited]
     
    The Aichi Biodiversity Targets (ABTs) of the Convention on Biological Diversity (CBD) define world targets for the conservation and sustainable use of biodiversity from 2011 through 2020. Post-2020 targets (post-ABTs) will be determined at the 15th Meeting of the Conference of Parties to the Convention (CBD-COP15) in 2020, and many studies on the challenges presented by these targets, and their effectiveness, have been conducted worldwide. In this article, we review possible approaches to be considered when setting these follow-up targets, such as specific, measurable, ambitious, realistic, time-bound (SMART) targets. Then, by focusing on Aichi Target 11 for protected areas as a case study, we discuss the challenges and concepts that could be incorporated into the new post-2020 targets, together with radical suggestions for modifying the current targets, using detailed examples in Japan. Lastly, we suggest that while nature preservation should be developed, other, approaches to nature, such as ecosystem-based disaster risk reduction, should also be implemented.
  • Yuichi Yamaura, Ayu Narita, Yoshinobu Kusumoto, Atsushi J. Nagano, Ayumi Tezuka, Toru Okamoto, Hikaru Takahara, Futoshi Nakamura, Yuji Isagi, David Lindenmayer
    BIOLOGY LETTERS 15 (5) 1744-9561 2019/05 [Refereed]
     
    Grassland ecosystems worldwide have been extensively converted to other land uses and are globally imperiled. Because many grasslands have been maintained by human activities, understanding their origin and history is fundamentally important to better contemporary management. However, existing methods to reconstruct past vegetation can produce contrasting views on grassland history. Here, we inferred demographic histories of 40 populations of four grassland forb species throughout Japan using high-resolution genome sequences and model-flexible demographic simulation based on the site frequency spectrum. Although two species showed a slight decline in population size between 100 000-10 000 years ago, our results suggest that population sizes of studied species have been maintained within the range of 0.5-2.0 times the most recent estimates for at least 100 000 years across Japan. Our results suggest that greater than 90% declines in Japanese grasslands and subsequent losses of grassland species in the last 100 years are geologically and biologically important and will have substantial consequences for Japanese biota and culture. People have had critical roles in maintaining disturbance-dependent grassland ecosystems and biota in this warm and wet forested country. In these contexts, disturbances associated with forest harvesting and traditional extensive farming have the potential to maintain grassland ecosystems and can provide important opportunities to reconcile resource production and conservation of grassland biodiversity.
  • Junjiro N. Negishi, Akira Terui, Badrun Nessa, Kazuki Miura, Takeaki Oiso, Keizo Sumitomo, Tomoko Kyuka, Mitsuaki Yonemoto, Futoshi Nakamura
    Landscape and Ecological Engineering 15 (2) 143 - 154 1860-1871 2019/04 [Refereed]
     
    Our understanding of ecosystem responses to exceedingly large rare flood events is currently limited. We report the resilience of aquatic community to a 100-year record-high flood, and how it varies depending on levels of water pollution, in a fourth-order gravel-bed river in northern Japan. We used data on riparian landscape structure, channel morphology, and community structure of aquatic fauna, which were collected in sites with and without effluent before (1 month–3 years) and after (10 months) the flood. Carbon and nitrogen stable isotope ratios of consumers and basal resources were measured only before (1 year) the flood. We observed aquatic food web with introduced rainbow trout (Oncorhynchus mykiss) as the top predator, with variable relative contributions of basal resources and their pathways to the rainbow trout, under the effects of water pollution. Biofilm-originating dietary carbon became the more dominant resource, with a slightly shorter food-chain length in the polluted sites. The flood led to a loss of riparian forest and a substantial increase in the proportion of exposed gravel bars (5–24%). While the average river-bed elevation changed a little, the localized scours of river bed down to > 2 m were observed with lateral shifts of channel thalweg. Despite the landscape-level physical and structural changes of ecosystem, aquatic community showed a remarkably high resilience exhibiting negligible changes in abundance, except in the polluted site where only fish abundance showed a slight decrease. This study suggests that the abundance of aquatic organisms in gravel-bed rivers is resilient to a flood of unprecedented magnitude in recent history.
  • Comparison of vulnerability to catastrophic wind between Abies plantation forests and natural mixed forests in northern Japan
    Junko Morimoto, Kosuke Nakagawa, Kohei T. Takano, Masahiro Aiba, Michio Oguro, Yasuto Furukawa, Yoshio Mishima, Kenta Ogawa, Rui Ito, Tetsuya Takemi, Futoshi Nakamura, Chris J. Peterson
    Forestry an International Journal of Forest Research 1 - 8 2019/02 [Refereed][Not invited]
  • Munehiro Kitazawa, Yuichi Yamaura, Masayuki Senzaki, Kazuhiro Kawamura, Masashi Hanioka, Futoshi Nakamura
    Ornithological Science 18 (1) 3 - 16 1347-0558 2019/01 [Refereed]
     
    Populations of birds inhabiting wetlands and grasslands are decreasing globally due to farmland expansion and subsequent agricultural intensification. In addition to conserving natural habitats, managing cultivated farmland and abandoned farmland are likely to be important future conservation measures; however, their relative suitability as avian habitat remains understudied. In this study, we evaluated five habitat types (wetland, pasture, cropland, abandoned farmland, and solar power plant) for openland birds in an agricultural landscape in central Hokkaido, northern Japan. Abandoned farmlands had bird species richness and total bird abundance values similar to those of wetlands. These values were generally higher in abandoned farmlands and wetlands than in croplands, pastures, and solar power plants. The per pair reproductive success of Stejneger's Stonechat Saxicola stejnegeri and the amount of its prey (arthropods) did not differ among the five habitat types. Three species (Black-browed Reed Warbler Acrocephalus bistrigiceps, Common Reed Bunting Emberiza schoeniclus, and Japanese Bush Warbler Cettia diphone) arrived earlier in wetlands than in other habitat types. These results suggest that, although protecting the remaining wetlands is of prime importance for the conservation of openland birds in agricultural landscapes, valuing and managing abandoned farmlands would be a promising alternative.
  • Akira Terui, Nobuo Ishiyama, Hirokazu Urabe, Satoru Ono, Jacques C. Finlay, Futoshi Nakamura
    PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 116 (3) 1067 - 1068 0027-8424 2019/01 [Refereed]
  • Hanioka Masashi, Yamaura Yuichi, Senzaki Masayuki, Yamanaka Satoshi, Kawamura Kazuhiro, Nakamura Futoshi
    AGRICULTURE ECOSYSTEMS & ENVIRONMENT 265 217 - 225 0167-8809 2018/10/01 [Refereed][Not invited]
     
    Expansion and intensification of agriculture have led to an immense decrease in biodiversity. However, the area of abandoned farmland has been increasing globally in recent years and is expected to provide novel habitats for various organisms. Despite the promising potential for biodiversity conservation in agricultural landscapes, few studies have compared biodiversity among multiple land use types, including abandoned farmland. We examined the effects of major land use types (wetland, grassland, forest, farmland, abandoned farmland) and the surrounding landscape openness (proportion of wetland/grassland in the surrounding area) on the abundance and species richness of bird communities and four functional groups (wetland, grassland, farmland, and forest species) in the agricultural landscape of central Hokkaido in northern Japan. The abundance of wetland/grassland species in abandoned farmland tended to be intermediate between those of their original habitats (wetland and grassland) and other land uses (forest and farmland), and to be positively associated with the landscape openness. The abundance of forest species tended to be higher in forest areas than in areas with other land use types and was not associated with the landscape openness. The abundance and species richness of the bird community were predicted to be high in large abandoned farmland areas surrounded by open land. For wetland species, whereas total abundance was predicted to be primarily mediated by landscape openness, species richness was predicted to be primarily mediated by the farmland abandonment area. The abandoned farmland in our study area would not currently have a high conservation value for forest birds. However, the abandonment of farmland surrounded by open land would significantly improve the conservation of wetland/grassland birds in the agricultural landscape. Given the decline in the area of grassland, wetland, and low-intensity farmland, farmland abandonment provides an opportunity to conserve and restore the declining populations of wetland and grassland birds.
  • Nakano Yurika, Senzaki Masayuki, Ishiyama Nobuo, Yamanaka Satoshi, Miura Kazuki, Nakamura Futoshi
    GLOBAL ECOLOGY AND CONSERVATION 16 2351-9894 2018/10 [Refereed][Not invited]
     
    Successful dispersal or movement between patches in fragmented landscapes is key for the survival and population persistence of wildlife. Despite the growing interest in the impacts of anthropogenic noise, how noise alters the permeability of different types of land cover to animal movement in fragmented landscapes is underappreciated. Here, we experimentally quantified the movement distances of a frog species in three types of land cover common to fragmented landscapes (lawns with or without canopy cover and artificial bare land) under two acoustic manipulations (traffic noise vs. a silent control). The results showed that the effects of noise on frog movements varied among land covers: with movement being impeded on bare land and unaffected on lawns with and without a closed canopy. These results suggest that anthropogenic noise and land cover types can interactively affect the functional connectivity of these anurans and increase our understanding of the complex ecological consequences of urbanization. Our finding emphasizes that the impacts of noise on animal movement in fragmented landscapes should be evaluated with consideration of land cover types.
  • V. Ruiz-Villanueva, L. Bürkli, B. Mazzorana, L. Mao, D. Ravazzolo, P. Iribarren, E. Wohl, F. Nakamura, M. Stoffel
    E3S Web of Conferences 40 2018/09/05 [Not refereed]
     
    Organic material (i.e., trees, branches, wood in general) is commonly neglected among the classical criteria to distinguish flow types, mostly due to the lack of direct observations of flows in which this load is significant. However, in forested basins, large amounts of wood can be transported. Here we define and characterize, for the first time, wood-laden flows and show that these flows may occur repeatedly in a river basin, carrying substantial amount of organic material, with probable impacts on the ecosystem and potential hazards. We propose a novel classification of flows from clear water to hypercongested wood debris flows, according to the composition of sediment, wood and water. Our results will contribute to a better understanding of flow phenomena in forested river basins, which may facilitate the design of better management strategies.
  • Masayuki Senzaki, Taku Kadoya, Clinton D. Francis, Nobuo Ishiyama, Futoshi Nakamura
    Functional Ecology 32 (8) 2054 - 2064 0269-8463 2018/08 [Refereed]
     
    Anthropogenic noise is widespread, and growing evidence suggests that it can negatively affect animals through many different mechanisms including masking of cues and signals, distraction, and aversion to noise. Acoustic masking has received the most attention from researchers and recent evidence suggests that masking effects can be mitigated by alteration of signal frequencies or amplitudes by signalers. Additionally, alteration can be a learned response via prior experience with noise exposure. However, it remains unclear whether distraction or aversive effects due to noise can be mitigated by prior experience with noise, especially among signal receivers. Here, we addressed this gap by separating mechanisms of noise disturbances on female phonotaxis towards male advertisement calls in anurans. To do this, we experimentally examined phonotaxis of gravid females that differ in their prior experience with noise under three acoustic manipulations: spectrally overlapping and non-overlapping noise that either mask or do not mask male advertisement calls respectively, plus a silent control. We confirm two experience-dependent responses of noisy-site individuals relative to quiet-site individuals: faster initiation of phonotaxis under non-overlapping noise and a stronger aversive response against overlapping noise. However, we showed that, for both noisy- versus quiet-site individuals, both overlapping and non-overlapping noise treatments resulted in delayed initiation and disorientation of phonotaxis relative to silent control treatments. Our study provides the first evidence to demonstrate that, although prior experience appears to mitigate the negative effects of distraction or aversion to noise, prior experience falls short of fully compensating for disrupted orientation through phonotaxis. Additionally, although most studies have emphasized masking of biologically relevant cues and signals as the most prominent mechanism by which noise negatively affects wild organisms, we show that non-overlapping noise, which cannot cause signal and cue masking, can have negative consequences via distraction or aversive responses. This finding suggests that noise impacts could extend well beyond contexts involving acoustic cue detection and discrimination and deserves increased attention by researchers. A plain language summary is available for this article.
  • Hanioka Masashi, Yamaura Yuichi, Yamanaka Satoshi, Senzaki Masayuki, Kawamura Kazuhiro, Terui Akira, Nakamura Futoshi
    BIODIVERSITY AND CONSERVATION 27 (8) 1831 - 1848 0960-3115 2018/07 [Refereed][Not invited]
     
    While wetlands have been converted into farmlands, large amounts of farmlands are now being abandoned, and this novel habitat is expected to be inhabited by species which depend on wetlands. Here we examined the effects of habitat and landscape variables on the densities of wetland bird species in abandoned farmlands. We surveyed birds in abandoned farmlands with different patch area, habitat, and landscape variables in Kushiro district, eastern Hokkaido, northern Japan. We also surveyed birds in 15 ha of the remaining wetlands as a reference habitat. We used abundance-based hierarchical community models (HCMs) to estimate patch-level estimates of abundance of each species based on sampling plots data that only partially covered the studied patches. We observed 14 wetland species and analyzed them with HCMs. Abandoned farmland patch areas had significant positive effects on the densities of two species. Tree densities and shrub coverage exerted positive and negative effects on some species. Amounts of surrounding wetland/grassland had positive effects on many species. Ensemble of species-level models suggested that 24.7 and 10.6 ha of abandoned farmlands would be needed to harbor a comparable total abundance and species richness in 15-ha wetlands, respectively. These required amounts can be increased/decreased depending on the covariates. The use of HCMs allows us to predict species- and community-level responses under varied conditions based on incomplete sampling data. A quantity of 1.6 times larger areas of abandoned farmlands may be required to restore wetland bird communities in eastern Hokkaido.
  • Terui Akira, Ishiyama Nobuo, Urabe Hirokazu, Ono Satoru, Finlay Jacques C, Nakamura Futoshi
    PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 115 (26) E5963 - E5969 0027-8424 2018/06/26 [Refereed][Not invited]
     
    Intraspecific population diversity (specifically, spatial asynchrony of population dynamics) is an essential component of metapopulation stability and persistence in nature. In 2D systems, theory predicts that metapopulation stability should increase with ecosystem size (or habitat network size): Larger ecosystems will harbor more diverse subpopulations with more stable aggregate dynamics. However, current theories developed in simplified landscapes may be inadequate to predict emergent properties of branching ecosystems, an overlooked but widespread habitat geometry. Here, we combine theory and analyses of a unique long-term dataset to show that a scale-invariant characteristic of fractal river networks, branching complexity (measured as branching probability), stabilizes watershed metapopulations. In riverine systems, each branch (i.e., tributary) exhibits distinctive ecological dynamics, and confluences serve as "merging" points of those branches. Hence, increased levels of branching complexity should confer a greater likelihood of integrating asynchronous dynamics over the landscape. We theoretically revealed that the stabilizing effect of branching complexity is a consequence of purely probabilistic processes in natural conditions, where within-branch synchrony exceeds among-branch synchrony. Contrary to current theories developed in 2D systems, metapopulation size (a variable closely related to ecosystem size) had vague effects on metapopulation stability. These theoretical predictions were supported by 18-y observations of fish populations across 31 watersheds: Our cross-watershed comparisons revealed consistent stabilizing effects of branching complexity on metapopulations of very different riverine fishes. A strong association between branching complexity and metapopulation stability is likely to be a pervasive feature of branching networks that strongly affects species persistence during rapid environmental changes.
  • Akira Terui, Junjiro N. Negishi, Nozomi Watanabe, Futoshi Nakamura
    ECOSYSTEMS 21 (4) 772 - 781 1432-9840 2018/06 [Refereed]
     
    Decades of research have revealed the crucial roles of cross-system energy flows (spatial subsidies) in mediating trophic interactions in recipient systems. Food web theory predicts that the responses of subsidized consumers are a key to understanding the net impacts of spatial subsidies on in situ prey/resources of recipient systems. However, less is known about the factors triggering the cascading biotic interactions across coupled ecosystems. Here, we quantify how riverine productivity (donor system) mediates terrestrial food web interactions through spatial subsidies to simplified gravel bar communities. Our comparative study in Japan indicated that higher algal biomass in aquatic systems led to increased supplies of emerging aquatic insects, which were associated with greater densities of terrestrial consumers (Carabid beetles) and enhanced consumption rates of supplemental in situ prey on gravel bars. Our results highlight the potential of donor productivity to drive cascading biotic interactions across coupled ecosystems. Because cross-system energy flows should originate, at least in part, from primary producers of donor systems, our fundamental finding may form the basis of future studies exploring the driving factors of cross-system trophic interactions.
  • Futoshi Nakamura
    Nihon Ringakkai Shi/Journal of the Japanese Forestry Society 100 (1) 1 - 2 0021-485X 2018 [Refereed]
  • Yoshiko Kobayashi, Yoshiyuki Masatomi, Futoshi Nakamura
    Biodiversity Conservation Using Umbrella Species 237 - 243 2191-0707 2018 [Refereed][Not invited]
  • Yoshiko Kobayashi, Futoshi Nakamura
    Biodiversity Conservation Using Umbrella Species 185 - 196 2191-0707 2018 [Refereed][Not invited]
  • Masahiro Nakaoka, Kenji Sudo, Mizuho Namba, Hideaki Shibata, Futoshi Nakamura, Satoshi Ishikawa, Mitsutaku Makino, Hiroya Yamano, Shin ichiro S. Matsuzaki, Takehisa Yamakita, Xiubo Yu, Xiyong Hou, Xiaowei Li, Jon Brodie, Keiichiro Kanemoto, Dan Moran, Francesca Verones
    Ecological Research 33 (1) 35 - 49 0912-3814 2018/01/01 [Refereed][Not invited]
     
    © 2017, The Ecological Society of Japan. The expanding economical activities have accelerated losses of biodiversity and ecosystem services, which are especially pronounced in Asia. To find solutions to stop these losses, a group of scientists studying both ecological and social sciences has launched an interdisciplinary research network, entitled TSUNAGARI (Trans-System, UNified Approach for Global and Regional Integration of social-ecological study toward sustainable use of biodiversity and ecosystem services). The project is based on two main perspectives: (1) integrating different disciplines of environmental research across multiple spatial scales, and (2) evaluating the importance of ecosystem connectivity between land and ocean for biodiversity and ecosystem services. The integrative studies have been started as follows: (1) integrating global-scale analyses of biodiversity and economy by developing GIS-based footprint analysis, (2) establishing the link between the studies of local good practices of ecosystem management and life cycle assessment on ecosystem good and services, (3) linking local-scale ecosystem studies to decision making processes for sustainable society by multiple stakeholders, and (4) upscaling local analyses of ecosystem processes to broad-scale analyses of ecosystem patterns. The proposed approaches are considered effective to solve problems that impede conservation of biodiversity and sustainable use of multiple ecosystem services in various situations although we also find some gaps such as regional biases in biodiversity data and involvement of different types of stakeholders. By overcoming the major bottlenecks, we believe the new integrated approaches will promote conservation and sustainable management of biodiversity and ecosystem services research, and contribute to advance decision-making processes from local communities to international levels.
  • Nagayama S, Nakamura F
    Limnology 19 (1) 7 - 20 1439-8621 2018 [Refereed][Not invited]
     
    This study examined the structure and function of habitats for fish, the contribution to fish populations, and the effects of channel modification on habitats and fish populations in the lowland meandering Shibetsu River, northern Japan. Electrofishing and environmental measurements were conducted in bank areas of habitats constituting natural meandering and modified reaches. All types of habitats in a meandering reach highly contributed to the fish population(s). In particular, the contributions of lateral and wood habitats to fish populations were generally high, despite the low spatial extent of these habitats. The modified reach was simplified and had fewer types of habitats with uniform currents, and there was a low abundance of most fish within these habitats. Abundance of each fish group (taxa) was negatively affected by the changes in the habitats and/or channel shortening (i.e., decrease in the absolute abundance of habitat) due to river modification, which was implemented during 1950–1978. This study suggests that the recovery of all the habitat types is important in meander restoration and that the changes in habitat types and abundance should be examined in monitoring meander restoration and channel shortening.
  • Nakano D, Nagayama S, Kawaguchi Y, Nakamura F
    Ecological Engineering 120 249 - 259 0925-8574 2018 [Refereed][Not invited]
     
    Restoration is needed to recover biodiversity in many lowland rivers under threat by human activities. It is commonly believed that stable large wood provides a suitable habitat for benthic fauna in lowland rivers with an unstable riverbed of fine sediment, as the wood creates benthic habitat via riverbed stabilization. In the present study, we installed large wood in the riverbed to test the stabilization effect on benthic fauna and to assess the differences in composition of macroinvertebrates between the large wood itself (branches) and the riverbed stabilized with the wood. Current velocity near the riverbed was substantially decreased by installing large wood. Abundance and richness of macroinvertebrates in the riverbed with large wood were significantly higher than those in riverbed without wood. Larval lampreys were also found in the riverbed but only with large wood present. Macroinvertebrate compositions differed between the stable riverbed and the branches. Chironominae (midges) was the most dominant taxon in all habitats, collector-gatherer mayflies Paraleptophlebia and Ephemerella were abundant in stable riverbed habitats, and collector-filterers such as Simulium, Cheumatopsyhce, and Hydropsyche in addition to the mayflies were also abundant in branch habitats. This study showed that large wood not only serves as habitat for benthic fauna but also creates habitat via riverbed stabilization. In lowland river restoration, installing large wood could have a significant effect on the provision and creation of stable habitats for benthic fauna.
  • Akira Terui, Keita Ooue, Hirokazu Urabe, Futoshi Nakamura
    PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES 284 (1866) 0962-8452 2017/11 [Refereed]
     
    Host dispersal is now recognized as a key predictor of the landscape-level persistence and expansion of parasites. However, current theories treat post-infection dispersal propensities as a fixed trait, and the plastic nature of host's responses to parasite infection has long been underappreciated. Here, we present a mark-recapture experiment in a single host-parasite system (larval parasites of the freshwater mussel Margaritifera laevis and its salmonid fish host Oncorhynchus masou masou) and provide, to our knowledge, the first empirical evidence that parasite infection induces size-dependent host dispersal in the field. In response to parasite infection, large fish become more dispersive, whereas small fish tend to stay at the home patch. The observed plasticity in dispersal is interpretable from the viewpoint of host fitness: expected benefits (release from further infection) may exceed dispersal-associated costs for individuals with high dispersal ability (i.e. large fish) but are marginal for individuals with limited dispersal ability (i.e. small fish). Indeed, our growth analysis revealed that only small fish hosts incurred dispersal costs (reduced growth). Strikingly, our simulation study revealed that this plastic dispersal response of infected hosts substantially enhanced parasite persistence and occupancy in a spatially structured system. These results suggest that dispersal plasticity in host species is critical for understanding how parasites emerge, spatially spread, and persist in nature. Our findings provide a novel starting point for building a reliable, predictive model for parasite/disease management.
  • Toshiya Yoshida, Sayoko Naito, Misato Nagumo, Natsumi Hyodo, Taiki Inoue, Hiromitsu Umegane, Haruka Yamazaki, Hisashi Miya, Futoshi Nakamura
    SUSTAINABILITY 9 (11) 2071-1050 2017/11 [Refereed][Not invited]
     
    The objective of forest management has become broader, and it is essential to harmonize timber production with conservation of the forest ecosystem. Selection cutting is recognized as a major alternative of clear-cutting, because it can maintain the complexity and heterogeneity of a natural forest; however, its long-term evaluations are limited. This study compared various attributes of stand structures, which are indicators of biodiversity and ecosystem carbon stock between managed and unmanaged blocks (12.6 ha area in total) in a natural mixed forest in Hokkaido, the northernmost island of Japan. We found that 30 years' implementation of single-tree selection did not affect the volume, size structure, species diversity nor spatial distribution of overstory trees in the managed stands. Also, the total carbon stock in the managed stands was almost equal to that of the unmanaged stands. In contrast, several structural attributes and indicator elements that are significant for biodiversity (such as large-diameter live trees, dead trees, cavities, epiphytic bryophytes, and some avian guilds) showed marked decrease in the managed stands. We conclude that it is required to leave these structures and elements to some extent for deriving the merit of the management as an alternative silvicultural regime in the region.
  • Satoshi Yamanaka, Takumi Akasaka, Yuki Yabuhara, Futoshi Nakamura
    AGRICULTURE ECOSYSTEMS & ENVIRONMENT 249 31 - 37 0167-8809 2017/11 [Refereed][Not invited]
     
    Depopulation trends in many developed regions are resulting in an increase in areas of abandoned farmland, which could provide an alternative habitat for species endangered by past conversion of wetlands for agriculture. Additionally, various spatial and temporal factors (landscape structure, local habitat quality, and abandonment age) could influence species composition in abandoned farmland. In this study, we explored the spatio-temporal effects of land abandonment on the species composition of wetland ground beetles (Coleoptera: Carabidae) to examine whether abandoned farmland can contribute to conserve wetland species' habitats. We first compared ground beetle assemblages among four land uses (grassland, wetland, and newly and previously abandoned farmland) in the Kushiro region, eastern Hokkaido, Japan. We then examined the factors influencing differences in wetland species composition between abandoned farmland and wetland. We found that the composition of wetland species in abandoned farmland was more similar to that of wetland than that of grassland. Our results also showed that soil moisture in abandoned farmland was positively related to the land abandonment age and that differences in wetland species composition between abandoned farmland and wetland were negatively related to both soil moisture and surrounding wetland area. Our findings suggest that abandoned farmland can serve as an alternative habitat for wetland ground beetles. Maintaining a high level of soil moisture in abandoned farmland and conserving the surrounding wetland could be an effective strategy for restoring natural habitats for these species.
  • Junko Morimoto, Masatoshi Shibata, Yuichiro Shida, Futoshi Nakamura
    Restoration Ecology 25 (6) 1005 - 1014 1061-2971 2017/11 [Refereed][Not invited]
     
    Natural restoration of historical wetland plant communities in fallow fields with a degraded seed bank has been assumed to be possible only if source populations of the target species are present adjacent to the abandoned fields and a high density of suitable microsites is available. However, few studies have monitored both factors simultaneously and verified this assumption. We hypothesized that plant communities that are similar to historical wetlands, including back marshes, back swamps, and bogs, will reestablish in abandoned pasturelands in cases when (1) gaps for new recruitment emerge, followed by the decline of pastures; and (2) seeds with longevity are supplied from the surrounding remnant plant communities of wetlands. We conducted a survey of vegetation and microsites in pastures, abandoned pastures, and reference wetlands followed by structural equation modeling to verify our hypothesis for the natural restoration of Phragmites australis–Phalaris arundinacea and Alnus japonica–Spiraea salicifolia communities. These communities represent historical back marshes and back swamps along a river. However, our hypothesis was not verified for the natural restoration of Vaccinium oxycoccos–Sphagnum spp. communities, which represent plant communities in historical bogs grown on acidic peat that are maintained by rainfall and fog. Our findings partly support our hypothesis that decline in pastures creates gaps and that cumulative seed dispersal from nearby remnant wetlands allows the original wetland plant communities to regenerate. Further case studies are needed to determine how the natural restoration of bog plant communities occurs.
  • Masanao Sueyoshi, Koji Tojo, Nobuo Ishiyama, Futoshi Nakamura
    AQUATIC SCIENCES 79 (4) 985 - 994 1015-1621 2017/10 [Refereed][Not invited]
     
    Agricultural activities have increased environmental homogenisation in stream ecosystems. These alterations reduce the availability of flow refugia during flooding and increase the effects of flood disturbances on aquatic insects. Thus, we examined the effects of the agricultural development (percentage of pasture cover within the catchment) and flood magnitude (ratio of shear stress at high flow to that at low flow) on the resistance indices measured by relative changes in taxon richness or abundance between pre- and post-flood (all insects, five orders and 31 dominant taxa) at 27 sites in the Kitamihorobetsu River, northern Japan. The resistance index of taxon richness decreased with increasing agricultural development, whereas that of the abundance of all insects decreased synergistically with increasing agricultural development and flood magnitude. Among 31 dominant taxa, the resistance indices of 20 taxa, generally belonging to Ephemeroptera, Plecoptera and Trichoptera, exhibited stronger negative relationships with agricultural development than with flood magnitude. By contrast, three Diptera taxa exhibited week negative relationships with agricultural development. These results showed that the interactive effect between agricultural development and flood magnitude was taxon dependent, but agricultural development could be detrimental to the resistance of most of the studied taxa, especially Ephemeroptera, Plecoptera and Trichoptera taxa. Additionally, agricultural developments in our study watersheds was relatively low (< 18% pasture cover), and nevertheless, apparent interacting effects with natural disturbance was detected. This implies that limited agricultural development along the river line can lower the resistance of instream insects to natural disturbances.
  • Masayuki Senzaki, Yuichi Yamaura, Yasushi Shoji, Takahiro Kubo, Futoshi Nakamura
    BIOLOGICAL CONSERVATION 214 1 - 5 0006-3207 2017/10 [Refereed][Not invited]
     
    Assessing the non-market value of biodiversity conservation is crucial to justify it economically. Using a choice experiment on wetland restoration in Hokkaido, northern Japan, we assessed the willingness of citizens to pay for different ecological statuses of a flagship species (absence, occasional occupancy, permanent occupancy, and breeding) and other principal conservation targets (establishment of a birdwatching station and wetland sizes). The results showed that the fundraising potential of the flagship species surpassed those of other conservation targets, irrespective of its ecological status, highlighting the superior publicity generated by charismatic species. We also showed that upgrading ecological status from occupancy to breeding did not result in additional financial support. Our study emphasizes that, although publicizing ecologically important statuses such as breeding is critical for successful conservation efforts, focusing much effort on flagship species rather than other conservation targets may be important to increase the economic value of conservation practices if such species are available.
  • Keita Ooue, Akira Terui, Hirokazu Urabe, Futoshi Nakamura
    Limnology 18 (3) 345 - 351 1439-8621 2017/08/01 [Refereed]
     
    Parasitic species often have detrimental effects on host growth and survival. The larvae of the genus Margaritifera (Bivalvia), called glochidia, are specialist parasites of salmonid fishes. Previous studies have reported negligible influences of the parasite on their salmonid hosts at natural infection levels. However, those studies focused mainly on their instantaneous effects (i.e., during the parasitic period). Given the time lag between physiological and somatic responses to pathogen infections, the effect of glochidial infection may become clearer during the post-parasitic period. Here, we examined whether the effect of glochidial infections of Margaritifera laevis on its salmonid host Oncorhynchus masou masou would emerge during the post-parasitic period. We performed a controlled aquarium experiment and monitored fish growth at two time intervals (i.e., parasitic and post-parasitic periods) to test this hypothesis. Consistent with previous observations, the effects of glochidial infection were unclear in the middle of the experiment (day 50; parasitic period). However, even with a natural glochidial load (48 glochidia per fish), we found a significant reduction in growth rates of infected fish in the extended period of the experiment (day 70; post-parasitic period). Our results suggest that examining only instantaneous effects may provide misleading conclusions about mussel–host relationships.
  • Masayuki Senzaki, Yuichi Yamaura, Futoshi Nakamura
    Journal of Wildlife Management 81 (6) 973 - 981 0022-541X 2017/08 [Refereed]
     
    Construction of buildings, and other types of land uses by humans can exert negative impacts on wildlife that live in the areas surrounding such developments (i.e., off-site impacts). To reduce or lessen such impacts, it is important to determine the biological metrics (e.g., abundance, breeding success) that are affected and at which spatial scales. We monitored the eastern marsh harrier (Circus spilonotus) breeding in wetland patches in northern Japan for 4 years and quantified its abundance (no. pairs) and breeding success (no. juveniles) in natural environments compared to artificial land uses in the surrounding areas. We developed a hierarchical model to simultaneously infer the effects of foraging habitats and artificial land uses on the numbers of pairs and juveniles. We found that the amount of foraging habitat within 0.5 km of wetland patches positively influenced the number of pairs per patch and that the amount of artificial land use within 2.0 km from the patches negatively influenced the number of pairs per patch and the number of juveniles per pair. The number of juveniles per patch was therefore affected by these 2 features and was most susceptible to increased land use by humans within 2.0 km from the patches. Our results can be used to predict the magnitudes of off-site impacts on eastern marsh harriers before any additional development occurs. To effectively manage off-site impacts, we highlight the importance of considering species abundance and the biological processes mediating breeding success that are possibly affected by different land uses. © 2017 The Wildlife Society.
  • Akimi Wakui, Masanao Sueyoshi, Ayuma Shimokawabe, Gaku Kudo, Junko Morimoto, Futoshi Nakamura
    Ecological Research 32 (2) 183 - 191 0912-3814 2017/03 [Refereed][Not invited]
     
    Algific talus is a micro-scale habitat type where highland plants (subalpine and alpine species) are found, disjunct from their typical range, in lowland forests. On algific talus, cold airflows from the interstices between talus fragments create a local microclimate colder than surrounding forests. Despite of the widely-known occurrence of unique vegetation on algific talus, critical environmental factors determining the distribution of highland species in this habitat type are unclear. In order to reveal the environmental factors enabling highland species to inhabit algific talus, we investigated the vegetation and environments of 26 algific talus sites and four reference (non-algific talus) sites in Hokkaido, northern Japan. Several algific talus sites were dominated by highland species, while some algific talus sites and all non-algific talus sites were dominated by lowland species. Community analysis based on detrended correspondence analysis (DCA) and canonical corresponding analysis (CCA) revealed that the algific talus sites dominated by highland species had lower ground temperature, more acidic soil, larger canopy openness, and less diverse vegetation than the sites dominated by lowland species. Highland plants might be maintained under conditions stressful for lowland plants, resulting in less competitive situation. Generalized linear models (GLM), used to evaluate the response of individual highland species to environmental factors, revealed that preferable environmental conditions for highland plants are highly species specific. These results indicate that the maintenance of diverse environments is crucial for the conservation of the unique vegetation and local populations of highland species in algific talus areas.
  • Atsushi Shimazaki, Yuichi Yamaura, Masayuki Senzaki, Yuki Yabuhara, Futoshi Nakamura
    Avian Conservation and Ecology 12 (1) 2017 [Refereed]
     
    Local scale movement behavior is an important basis to predict large-scale bird movements in heterogeneous landscapes. Here we conducted playback experiments using mobbing calls to estimate the probability that forest birds would cross a 50-m urban area during three seasons (breeding, dispersal, and wintering seasons) with varying amounts of tree cover, building area, and electric wire density. We examined the responses of four forest resident species: Marsh Tit (Poecile palustris), Varied Tit (Sittiparus varius), Japanese Tit (P. minor), and Eurasian Nuthatch (Sitta europaea) in central Hokkaido, northern Japan. We carried out and analyzed 250 playback experiments that attracted 618 individuals. Our results showed that tree cover increased the crossing probability of three species other than Varied Tit. Building area and electric wire density had no detectable effect on crossing probability for four species. Seasonal difference in the crossing probability was found only for Varied Tit, and the probability was the highest in the breeding season. These results suggest that the positive effect of tree cover on the crossing probability would be consistent across seasons. We therefore conclude that planting trees would be an effective way to promote forest bird movement within an urban landscape.
  • 石山信雄, 永山滋也, 岩瀬晴夫, 赤坂卓美, 中村太士
    応用生態工学 19 (2) 143 - 164 2017 [Refereed][Not invited]
  • 中村太士, 中村太士, 島谷幸宏, 島谷幸宏, 西廣淳, 西廣淳, 大槻順朗, 大槻順朗, 厳島怜, 厳島怜, 山田浩之, 山田浩之
    応用生態工学 応用生態工学会 19 (2) 259‐267(J‐STAGE) - 267 1344-3755 2017 [Refereed][Not invited]
  • Masanao Sueyoshi, Takumi Akasaka, Terutaka Mori, Nobuo Ishiyama, Tomoaki Kawamoto, Yuuya Takegawa, Mikio Inoue, Hiromune Mitsuhashi, Yoichi Kawaguchi, Norio Onikura, Yo Miyake, Izumi Katano, Futoshi Nakamura
    Japanese Journal of Conservation Ecology 21 (2) 167 - 180 1342-4327 2016/11 [Refereed][Not invited]
     
    With rapid declines in global riverine biodiversity, conservation is needed on a nationwide scale. Since 1990, the National Census on River Environments (NCRE) has collected meaningful data on riverine organisms and environments in Japan. However, there are several issues with using the NCRE database for scientific studies. In this study, we summarised issues related to the NCRE database, and used the 3rd NCRE dataset (2001-2005) to evaluate nationwide trends in species richness and the rarity of fishes (primarily freshwater and diadromous fishes) and taxon richness and the rarity of benthic animals (aquatic insects and shellfishes). First, we summarised data quality (e.g. monitoring sites and season) and data formatting issues (e.g. site name and species name). Second, we mitigated these potential issues as thoroughly as possible and tested the relationships of species (or taxon) richness and rarity with latitude using generalised linear models. We found that species and taxon richness showed different latitudinal distributions between primarily freshwater and diadromous fishes and between aquatic insects and shellfishes. In contrast, rarities showed spatial congruence with species diversity, suggesting that more species and rare species could be conserved in the same regions.
  • Shimazaki, A., Yamaura, Y., Senzaki, M., Yabuhara, Y., Akasaka, T., Nakamura, F.
    Urban Forestry and Urban Greening 19 167 - 175 1618-8667 2016/09/01 [Refereed][Not invited]
     
    The urban matrix was recently shown to be a mosaic of heterogeneous dispersal habitats. We conducted a playback experiment of mobbing calls to examine the probabilities of forest birds to cross a distance of 50 m over urban matrix with different land-cover types in an urban area. We treated the reciprocal of the crossing probabilities as a movement resistance for forest birds. We drew resistance surfaces based on the land-cover maps of urban Sapporo. We applied a circuit theory to examine the relative role of a detour route consisting of a riparian corridor and urban matrix for dispersing forest bird individuals from continuous forest to an isolated green space in the midst of an urban area. Our results showed that wood cover had the highest crossing probability, while open land (grassland and pavement) had the lowest probabilities. Buildings and water surface displayed an intermediate probability. Resistance surfaces and flow maps at 25- and 50-m resolutions were very similar and suggested that dispersing individuals are likely to use the intervening building areas that dominate the urban matrix rather than detour through riparian corridors. Our results showed the useful combination of experimental approaches and circuit theory, and the importance of the spatial configuration of corridors, as well as the composition and management of dispersal habitats, to landscape connectivity.
  • 河川水辺の国勢調査を保全に活かす —データが持つ課題と研究例
    末吉正尚, 赤坂卓美, 森照貴, 石山信雄, 川本朋慶, 竹川有哉, 井上幹生, 三橋弘宗, 河口洋一, 鬼倉徳雄, 三宅洋, 片野泉, 中村太士
    保全生態学研究 21 1592 - 1602 2016/09 [Refereed][Not invited]
  • Kawamura Kazuhiro, Yamaura Yuichi, Senzaki Masayuki, Yabuhara Yuki, Akasaka Takumi, Nakamura Futoshi
    ORNITHOLOGICAL SCIENCE 15 (2) 203 - 212 1347-0558 2016/07 [Refereed][Not invited]
     
    Although the relative importance of land use and climate to large-scale bird distributions has received great attention, it is difficult to separate the effects of land use and climate, and there are few studies on bird abundance distributions on a large scale. Here, we examined the effects of land use and climate on the abundance of the nocturnal Jungle Nightjar Caprimulgus indicus in Hokkaido, northern Japan. We chose 125 sampling sites with low correlations (|r| <0.58) between land use and climate, and combined a playback method with a hierarchical model (N-mixture model). We thereby accounted for the possibility that we could not detect all individuals during the field survey. Results show that Jungle Nightjar abundance was greater at sites within a 4−km radius of moderate forest cover (~75%) and with high average temperatures during the breeding season. Moreover, the effects of land-use were greater than those of climate. Mapping predictions of Jungle Nightjar abundance indicated that suitable areas are distributed in southern and central Hokkaido and around the margins of montane zones. Factoring in the covariation of land use and climate, land use may be the most important driver of the distribution of the Jungle Nightjar in Hokkaido.
  • Sueyoshi, M., Ishiyama, N., Nakamura, F.
    Landscape and Ecological Engineering 12 (2) 187 - 196 1860-1871 2016/07 [Refereed][Not invited]
     
    Several studies report the decline of β diversity caused by agricultural impacts in river ecosystems. However, the susceptible scale of β diversity to agricultural impacts and the indirect effects on β diversity within hierarchically nested ecosystems are unclear. We first tested the hypothesis that β diversity between microhabitats is significantly influenced by agricultural land use. We also examined the indirect effects of agricultural land use on α and β diversities at the microhabitat scale. Twelve microhabitat samples (25 cm2) were collected at 27 reaches within Kitamihorobetsu River, Japan. All reaches were classified into three agricultural intensities based on pasture area (low, middle, and high), and their hierarchical diversities (microhabitat, reach, and catchment) were calculated using additive partitioning. Indirect effects were demonstrated by structural equation modelling using indirect and direct environmental gradients. The α and β diversities at the microhabitat scale decreased significantly with agricultural intensity. Increasing pasture cover within catchments showed a negative correlation with habitat heterogeneity and water quality (habitat homogenization and water degradation) and a positive correlation with sand cover on streambeds (sedimentation of fine particles). The α diversity decreased with sedimentation of fine particles, and the β diversity decreased with habitat homogenization and water degradation. Our findings suggest that species diversity of aquatic insects at the microhabitat scale would be susceptible to agricultural land use. Furthermore, we emphasize that the diversity index used to evaluate restoration projects should be carefully selected because influential abiotic factors were different between α and β diversities.
  • Ishiyama, N., Sueyoshi, M., Watanabe, N., Nakamura, F.
    Aquatic Conservation: Marine and Freshwater Ecosystems 26 (3) 416 - 428 1052-7613 2016/06 [Refereed][Not invited]
     
    Farmland expansion is a growing threat to aquatic biodiversity. Identifying conservation priority areas in agricultural landscapes is a key issue in freshwater ecology and information on the spatial variability of aquatic biodiversity is vital for prioritization. This study examined patterns of farmland fish assemblages across various water-body types in northern Japan to develop an effective management plan for freshwater fishes. Water bodies were classified into five types: small lowland streams, small upland streams, large rivers, man-made ditches, and wetland ponds, and native fishes were collected from each type. The contribution of fish diversity between water-body types (β2) to the regional fish diversity (γ) was investigated through additive diversity partitioning. Within each water-body type, the contributions of between-site diversity (β1) and within-site diversity (α1) were also examined. The assemblage composition, species richness, and rarity were compared among the water-body types. The assemblage composition differed significantly among most of the water-body types, which indicated that the landscape classification was appropriate for representing spatial variations in fish diversity. Additive diversity partitioning revealed that the contributions of β1 and β2 to γ fish diversity were relatively high at 38.2% and 37.3%, respectively, followed by a 24.5% contribution of α1 diversity. This finding demonstrates that the best strategy for conserving regional farmland fish diversity is to preferentially select areas containing various water-body types as a conservation unit. Among the water-body types, ditches and streams exhibited the higher contribution ratio for β1 diversity, whereas the contribution of β1 diversity was lower in wetland ponds. The differences in the contribution of β1 diversity might be attributed to human-induced factors, such as habitat fragmentation or shrinking. These results emphasize that further studies are needed to clarify the factors influencing the β1 diversity of farmland fish to develop better management strategies for each water-body type. Copyright © 2015 John Wiley & Sons, Ltd.
  • Matsubayashi, J., Otsubo, K., Morimoto, J.O., Nakamura, F., Nose, T., Tayasu, I.
    Biological Journal of the Linnean Society 119 (1) 99 - 105 0024-4066 2016/03 [Refereed][Not invited]
     
    The brown bear (Ursus arctos) population on Etorofu Island, Southern Kuril Islands, has several unique morphological features: (1) the presence of white-pelage bears within the population and (2) a larger body size than bears on a larger neighbour island, Hokkaido Island. Nevertheless, little ecological information is available about Etorofu brown bears. In the present study, we reveal the unique feeding habits of Etorofu brown bears and suggest that their unique morphological features and diet are related. The feeding habits of brown bears on Etorofu Island were assessed using carbon, nitrogen, and sulfur stable isotope analysis, and their feeding habits were compared with those of bears on the eastern side of Hokkaido Island. According to the stable isotope analysis, the dependence on salmon is great for bears on Etorofu but only slight for bears on Hokkaido. Our results suggest that the feeding habits of Etorofu brown bears may explain their unique morphological features because a white pelage colour confers an advantage when catching salmon, and a carnivorous diet can make their body size larger. The variation in feeding habits can be an important driver of the speciation and evolution of animals.
  • Yamaura Yuichi, Shoji Yasushi, Mitsuda Yasushi, Utsugi Hajime, Tsuge Takahiro, Kuriyama Koichi, Nakamura Futoshi
    The Japanese Forest Society Congress 日本森林学会 127 43 - 43 2016 
    [in Japanese]
  • Futoshi Nakamura, Yukihiro Shimatani, Jun Nishihiro, Kazuaki Ohtsuki, Rei Itsukushima, Hiroyuki Yamada
    Ecology and Civil Engineering 119 (2) 259 - 267 1344-3755 2016 [Refereed]
  • Yamaura, Y., Shoji, Y., Mitsuda, Y., Utsugi, H., Tsuge, T., Kuriyama, K., Nakamura, F., Alves, J.
    Journal of Applied Ecology 53 (4) 1117 - 1126 0021-8901 2016 [Refereed]
     
    For biodiversity conservation to be an effective and significant social investment, non-marketed values of biodiversity conservation and its associated opportunity costs should be evaluated in monetary terms. In this study, we measured the willingness to pay (WTP) for bird abundance using a choice experiment (CE) based on the random utility model. We performed a cost-benefit analysis to identify the optimal proportion of broadleaved trees in conifer plantations on a volume basis to maximize the social benefits of bird conservation and wood production. The results suggested that respondents to the CE were not satisfied with their current situation and preferred an increase in bird abundance. However, the estimated WTP indicated diminishing returns of bird conservation. More specifically, WTP first greatly increased before gradually experiencing decreasing marginal values, reaching its peak and finally decreasing slightly with increasing bird abundance. Optimization analyses indicated that when the relationship between bird abundance and broadleaved tree proportion was convex, semi-natural plantations with nonzero broadleaved tree proportion (002-022) were always optimal options. When the relationship was linear, optimal broadleaved tree proportion ranged from 0 to 078 and was greatly affected by wood values. When the relationship was concave, there were only two optimal broadleaved tree proportions: a very high proportion (approximately 090) and the lowest possible proportion (0). When the convex and concave relationships approached the linear form, comparable benefits could be attained across broad ranges of broadleaved tree proportion both within and across the relationships. In such cases, it would be useful to increase the likelihood of a feasible land-use strategy of either land sparing or land sharing in order to be successful.Synthesis and applications. It can be difficult to set quantitative targets in biodiversity conservation solely on an ecological basis, and social benefits of biodiversity conservation can create diminishing returns in many situations. The framework we propose shows how to reconcile resource production and biodiversity conservation in the real world.
  • Senzaki, M., Yamaura, Y., Francis, C.D., Nakamura, F.
    Scientific Reports 6 2016 [Refereed]
     
    Anthropogenic noise has been increasing globally. Laboratory experiments suggest that noise disrupts foraging behavior across a range of species, but to reveal the full impacts of noise, we must examine the impacts of noise on foraging behavior among species in the wild. Owls are widespread nocturnal top predators and use prey rustling sounds for localizing prey when hunting. We conducted field experiments to examine the effect of traffic noise on owls' ability to detect prey. Results suggest that foraging efficiency declines with increasing traffic noise levels due to acoustic masking and/or distraction and aversion to traffic noise. Moreover, we estimate that effects of traffic noise on owls' ability to detect prey reach >120 m from a road, which is larger than the distance estimated from captive studies with bats. Our study provides the first evidence that noise reduces foraging efficiency in wild animals, and highlights the possible pervasive impacts of noise.
  • Yamaura, Y., Schmaljohann, H., Lisovski, S., Senzaki, M., Kawamura, K., Fujimaki, Y., Nakamura, F.
    Journal of Avian Biology 48 (2) 197 - 202 0908-8857 2016 [Refereed]
     
    The East Asian-Australian Flyway spans from north Asia to Australia and is the world's richest birds' flyway because it involves > 40% of global migratory bird species. However, information is lacking on individual migratory routes and non-breeding grounds for small land birds using this flyway. Here, we present the first migration tracks of the songbird Stejneger's stonechat Saxicola stejnegeri from this part of the world using light-level geolocators. This species depends on grasslands during the entire annual cycle and was captured and equipped with tracking devices in Hokkaido, northern Japan. All individuals traveled through southern Primorye or eastern Heilongjiang (Russia/China) before flying southward via central China toward their major non-breeding grounds in southeast Asia (China, Laos, Cambodia, Thailand, and Vietnam). Individual stonechats spent 42-70 d en route during their autumn migration. Both the major non-breeding grounds and the stopover sites are likely to pose challenges to the persistence of this species, because these habitats are currently degraded and will likely be lost in the near future due to intensified agriculture and the establishment of permanent croplands. Moreover, the areas used by Stejneger's stonechat during migration largely overlapped with illegal trapping areas in northeastern China.
  • Shimokawabe, A., Yamaura, Y., Sueyoshi, M., Kudo, G., Nakamura, F.
    Alpine Botany 126 (2) 143 - 151 1664-2201 2016 [Refereed]
     
    Local cool spots (wind-holes) in lowland areas of midlatitudes may act as microrefugia for cold-adapted species outside of their typical alpine habitats. We examined the genetic structure of Vaccinium vitis-idaea, a common alpine species in Japan, in eight lowland wind-hole and five surrounding alpine populations. We collected leaf samples and genotyped seven microsatellite loci. Clonal patches (genets) were common in almost all populations. An analysis of annual shoot growth suggested that individuals in the wind-hole populations were long-lived (>500 years old). Genetic diversity (allelic richness) and differentiation (FST) of the wind-hole populations were lower and higher than those of the alpine populations, respectively. No significant isolation-by-distance trend in the genetic structure was detected for the wind-hole or alpine populations. All wind-hole populations had negative inbreeding coefficients (FIS), suggesting no tendency toward homozygosity due to inbreeding, regardless of the small populations geographically isolated from the large alpine populations. Therefore, wind-holes may harbor genetically isolated but stable populations due to clonal growth, limited gene flow, and abortion of selfed seeds by early acting inbreeding depression. Analysis of molecular variance demonstrated that genetic variations among and within populations contributed more to regional genetic diversity than those between wind-hole and alpine populations, suggesting that the wind-hole and alpine populations are important for maintaining the genetic diversity of midlatitude V. vitis-idaea populations. On the other hand, Bayesian clustering showed that some wind-hole populations geographically close to the alpine populations had mixed genetic compositions of the alpine and wind-hole populations.
  • Kajihara, K., Yamaura, Y., Soga, M., Furukawa, Y., Morimoto, J., Nakamura, F.
    Urban Ecosystems 19 (1) 1 - 12 1083-8155 2016 [Refereed][Not invited]
     
    Biodiversity conservation and restoration in cities is a global challenge for the 21st century. Unlike other common ecosystems, urban landscapes are predominantly covered by gray, artificial structures (e.g., buildings and roads), and remaining green spaces are scarce. Therefore, to conserve biodiversity in urban areas, understanding the potential conservation value of artificial structures is vital. Here, we examined factors influencing the distribution of ferns in building gaps, one of the more common artificial structures, in urban Sapporo, northern Japan. We observed 29 fern species, which corresponds to 30 % of all fern species previously recorded in Sapporo. The four dominant species were Equisetum arvense, Matteuccia struthiopteris, Dryopteris crassirhizoma, and Athyrium yokoscense. Statistical analyses showed that their distribution patterns in building gaps were associated with both local- and landscape-scale environmental factors. Although ground cover type and distance from continuous forests were the most important determinants, other factors such as the amount of solar radiation, habitat age (years after building development), and urban district type also affected fern distribution. These results suggest that building gaps act as an important habitat for ferns in highly urbanized landscapes. Policy makers and city planners should therefore not overlook these cryptic habitats. Clarifying the ecological functions of artificial structures will both further our understanding of novel ecosystems and develop a new framework for conserving and restoring biodiversity in human-modified landscapes.
  • Seo, J.I., Nakamura, F., Chun, K.W., Kim, S.W., Grant, G.E.
    Hydrological Processes 29 (24) 5044 - 5057 0885-6087 2015/11 [Refereed][Not invited]
     
    Large wood (LW) plays an important role in river ecosystems, but LW-laden floods may cause serious damage to human lives and property. The relationship between precipitation patterns and variations in LW distribution and export at the watershed scale is poorly understood. To explore these linkages, we examined differences in LW distribution as a function of channel morphologies in six watersheds located in southern and northern Japan and analysed the impacts of different precipitation patterns on the fluvial export of LW from river catchments. In southern Japan, intense rainfalls caused by typhoons or localized torrential downpours initiate landslides and debris flows that introduce massive amounts of LW into channels. Gravel bars formed by frequent flood events are widely prevalent, and the LW temporarily stored on these bars is frequently moved and/or broken into smaller pieces by floods. In these systems fluvial export of LW is supply-limited, with smaller accumulations and shorter residence times than in northern Japan. Conversely, in northern Japan, where typhoons and torrential downpours rarely occur, LW is mostly recruited by bank erosion, tree mortality and windthrow into channels, rather than by landslides and debris flows. Recruited pieces accumulate in log jams on valley floors, particularly on floodplains supporting mature forests, resulting in larger accumulations and longer residence times. In these watersheds fluvial export of LW is transport-limited, and the pieces gradually decompose during long-term storage as log jams. Copyright (C) 2015 John Wiley & Sons, Ltd.
  • Ishiyama, N., Koizumi, I., Yuta, T., Nakamura, F.
    Freshwater Biology 60 (4) 733 - 744 0046-5070 2015/04 [Refereed][Not invited]
     
    The management of population size and genetic diversity in fragmented landscapes is the central issue in conservation biology. Functional connectivity between remnant habitat patches affects these parameters. However, the functional connectivity for genetic diversity would be characterised by a greater spatial scale than population size even within the same habitat network. The reason for this difference is that while dispersal frequency generally decreases with increasing distance, only a few immigrants may effectively contribute to gene flow, whereas a certain number of dispersers may be required to influence population abundance. Here, we investigated the effects of habitat network structures on population abundance and genetic diversity of the ninespine stickleback, Pungitius pungitius, in remnant wetland ponds in northern Japan. We tested (i) whether both population abundance and genetic diversity are positively related not only to habitat size but also to connectivity and (ii) whether the dispersal effect extends to greater spatial scales in genetic diversity than in population size. We employed a graph theoretical index to measure the degree of pond connectivity. This index can evaluate the connectivity threshold distance above which individuals cannot disperse and clarify the difference in the spatial scale of effective dispersal between population abundance and genetic diversity. Pond connectivity significantly affected the spatial variation of both population abundance and genetic diversity. In contrast, pond size was related only to population abundance. As we predicted, the connectivity threshold distance for genetic diversity was more than two times greater than that for population abundance (12.5km versus 5km, respectively). Our findings indicate that the landscape managers should consider various spatial scales as a conservation unit for the management of a habitat network in accordance with the conservation targets that they establish. We also found that small artificial agricultural ditches and streams may play important roles in sustaining the population networks of wetland organisms.
  • Matsubayashi, J., Morimoto, J.O., Tayasu, I., Mano, T., Nakajima, M., Takahashi, O., Kobayashi, K., Nakamura, F.
    Scientific Reports 5 2015/03 [Refereed][Not invited]
     
    Human activities have had the strongest impacts on natural ecosystems since the last glacial period, including the alteration of interspecific relationships such as food webs. In this paper, we present a historical record of major alterations of trophic structure by revealing millennium-scale dietary shifts of brown bears (Ursus arctos) on the Hokkaido islands, Japan, using carbon, nitrogen, and sulfur stable isotope analysis. Dietary analysis of brown bears revealed that salmon consumption by bears in the eastern region of Hokkaido significantly decreased from 19% to 8%. In addition, consumption of terrestrial animals decreased from 56% to 5% in western region, and 64% to 8% in eastern region. These dietary shifts are likely to have occurred in the last approximately 100-200 years, which coincides with the beginning of modernisation in this region. Our results suggest that human activities have caused an alteration in the trophic structure of brown bears in the Hokkaido islands. This alteration includes a major decline in the marine-terrestrial linkage in eastern region, and a loss of indirect-interactions between bears and wolves, because the interactions potentially enhanced deer predation by brown bears.
  • Yabuhara, Y., Yamaura, Y., Akasaka, T., Nakamura, F.
    River Research and Applications 31 (1) 109 - 119 1535-1459 2015 [Refereed]
     
    As anthropogenic impacts on riverine ecosystems expand, both aquatic and terrestrial ecosystems are influenced over large spatiotemporal scales. We predicted how riparian bird communities changed in response to long-term changes in floodplain landscapes such as woodland expansion (i.e. rapid increases in vegetation cover on gravel bars and the progress of vegetation succession due to a decrease in the frequency and magnitude of flood disturbance). To test the hypothesis that woodland expansion after dam construction reduces the abundance of gravel bar-nesting birds and increases the abundance of forest-nesting birds, we estimated historical changes between past and present bird abundances using species distribution models across multiple rivers that were either unregulated or regulated by dams. We created past and present vegetation maps from remote sensing images and used habitat quantities as explanatory variables in the species distribution models. As we hypothesized, the estimated abundance of gravel bar-nesting birds decreased and that of forest-nesting birds increased because of woodland expansion in some regulated rivers. This suggests that anthropogenic alterations of riverine conditions (e.g. dam construction) can affect terrestrial ecosystems (e.g. riparian bird communities) through changes in floodplains (e.g. woodland expansion). In addition, our findings highlight the efficacy of combining spatial and temporal analyses when examining long-term ecological dynamics.
  • Ishiyama, N., Sueyoshi, M., Nakamura, F.
    Royal Society Open Science 2 (7) 2015 [Refereed]
     
    Understanding how human-altered landscapes affect population connectivity is valuable for conservation planning. Natural connectivity among wetlands, which is maintained by floods, is disappearing owing to farmland expansion. Using genetic data, we assessed historical changes in the population connectivity of the ninespine stickleback within a human-altered wetland system. We predicted that: (i) the contemporary gene flow maintained by the artificial watercourse network may be restricted to a smaller spatial scale compared with the gene flow preceding alteration, and (ii) the contemporary gene flow is dominated by the downstream direction owing to the construction of low-head barriers. We evaluated the potential source population in both timescales. Seventeen studied populations were grouped into four genetically different clusters, and we estimated the migration rates among these clusters. Contemporary migration was restricted to between neighbouring clusters, although a directional change was not detected. Furthermore, we consistently found the same potential source cluster, from past to present, characterized by large amounts of remnant habitats connected by artificial watercourses. These findings highlight that: (i) artificial connectivity can sustain the short-distance connectivity of the ninespine stickleback, which contributes to maintaining the potential source populations; however, (ii) population connectivity throughout the landscape has been prevented by agricultural developments.
  • Senzaki, M., Yamaura, Y., Nakamura, F.
    Biological Conservation 191 460 - 468 0006-3207 2015 [Refereed]
     
    Given the global reduction in biodiversity, conservation actions must occur even with only a partial understanding of the distribution and abundance of species in various locales. The concept of surrogate species, those whose protection affords the protection of other species, is considered a conservation short-cut. Although surrogate species have been used as practical conservation tools, whether they serve as indicators of the reproductive output of other species is still unknown. We hypothesized that the reproductive output of the eastern marsh harrier (Circus spilonotus) can serve as a surrogate for both the adult abundance and reproductive output of sympatric birds. In a fragmented wetland landscape (approximately 211.60km2), we measured the reproductive output of harriers for 3years and conducted replicated counts of the adults and juveniles of other wetland bird species in wetland patches that varied in harrier reproductive output. We used playbacks of mobbing calls in replicated counts and accounted for imperfect detection using an N-mixture model. We modeled adult and juvenile abundances for 10 and 7 species, respectively, and showed that the reproduction-based habitat quality of the marsh harrier (cumulative numbers of both years occupying the habitat and chicks produced) was positively associated with adult abundances in four species and with juvenile abundances in five species. We suggest that areas with high reproductive output of several sympatric bird species could be selected based on the reproduction-based habitat quality of the marsh harrier. Furthermore, the approach combining the playback of mobbing calls and N-mixture models enabled us to estimate juvenile abundances for many bird species on a landscape scale over a short period of time.
  • Ahn, Y.-S., Kasahara, T., Otsuki, K., Wakana, I., Satoh, H., Nakamura, F., Takamura, N., Einarsson, Á., Park, C.-M., Seo, J.-I., Chun, K.-W.
    Journal of the Faculty of Agriculture, Kyushu University 60 (1) 225 - 233 0023-6152 2015 [Refereed]
     
    The purpose of this study was to examine the long-term fluctuation in remains of Aegagropila linnaei associated with phytoplankton dynamics and sediment accumulation in Lake Takkobu, northern Japan. A. linnaei is a green alga requiring good light conditions (low phytoplankton production and a low density of fine sediment particles) for growth. Six lake sediment core samples were obtained, and lake sediment-core samples contained two tephra layers as Ko-c2 (1694) and Ta-a (1739). Fresh tephra deposition is the source of phosphorus in the lake, and induces an increase in phytoplankton. For the period 1694-1739, low sediment accumulations and low phytoplankton productions were observed, and A. linnaei remains were low, likely due to nutrient deficiency. Ko-c2 tephra deposition had no detectable influence on phytoplankton and A. linnaei dynamics, as insufficient tephra was deposited to induce a nutrient deficiency. However, phytoplankton productivity was attributed to Ta-a tephra deposition, which was at a higher influx than that of Ko-c2, in addition to human activities, such as deforestation and agricultural development. A. linnaei remains in 1739-1898 were increased despite the enhanced phytoplankton productivity caused by Ta-a tephra deposition. This evidence indicates that a phytoplankton impact on the transparency from 1739-1898 was probably insignificant, but the released nutrient from Ta-a tephra acted as a stimulus to make the A. linnaei grow. Therefore, A. linnaei existence depends on interaction between light conditions and sediment accumulation as well as nutrient conditions. Human activities after 1898 have directly influenced increased phytoplankton productivity and sediment accumulation, and result in A. linnaei degraded. Moreover, A. linnaei remains mainly were concentrated in sediment from northern zone close to lake outflow because their spherical form and free-floating filaments tend to be moved by water flow. In recent years, the distribution of A. linnaei in the lake was reduced due to the shading effect caused by the increase in phytoplankton production and the attenuation of sunlight by high sediment accumulation.
  • Shimokawabe, A., Yamaura, Y., Akasaka, T., Sato, T., Shida, Y., Yamanaka, S., Nakamura, F.
    PLoS ONE 10 (8) e0135732  1932-6203 2015 [Refereed][Not invited]
     
    It has recently been proposed that microrefugia played an important role in species survival during past climate change events. However, the current distributions of microrefugia remain largely unknown. Wind-hole sites are areas affected by preferential flows of cool air generated in interstitial spaces created by rock fragments or colluvia. Alpine plant species occurring in lowland wind-hole sites isolated from alpine zones may be relicts of the last glacial period. Hokkaido, northern Japan, is known to contain many wind-hole sites in which alpine plant species can occur. Here we surveyed 55 wind-hole sites in the Kitami region, eastern Hokkaido, and observed two alpine plant species (lingonberry, Vaccinium vitis-idaea, and Labrador tea, Rhododendron groenlandicum ssp. diversipilosum var. diversipilosum) in 14 wind-hole sites. Statistical modeling showed that wind-hole sites are likely to occur in areas with high maximum slope angles and volcanic rock cover, and concave surfaces. Our predictions of wind-hole site distributions suggest that such topographic conditions are common in our study area, and that many undiscovered wind-hole sites exist. Ignoring microhabitats may greatly underestimate species distributions in topographically complex regions, and dispersed cool spots may also function as stepping stones and temporal habitats for cold-adapted species. Because these localized unique habitats usually occur in economically unproductive sites, identifying and protecting potential microrefugia (cool spots) would be a robust and cost-effective mitigation of climate change impacts.
  • Yamanaka, S., Akasaka, T., Yamaura, Y., Kaneko, M., Nakamura, F.
    Ecological Indicators 48 593 - 598 1470-160X 2015/01 [Refereed][Not invited]
     
    Biological indicator methods represent one of the most effective and widely used strategies for understanding the influences of environmental degradation on biodiversity in various landscapes. Researchers and land managers generally assume that the present distributions of biological indicator species are influenced by the current environment. However, recent studies have suggested the importance of past environments to species distributions (i.e., a time lag between changes in species distribution and habitat alterations). Therefore, it is necessary to understand the effects of past environments on the distributions of indicator species.We conducted a survey on the Tokachi Plain in Hokkaido, Japan. We targeted two taxa that have been widely used as indicator species (carabid beetles and bats) and investigated whether past landscape environments influenced their present distributions. We showed that past landscape environments (5 decades prior to the present) influenced the distributions of some ecological trait groups in each taxon (large body size for carabid beetles and a 25 kHz peak echolocation frequency for bats) and that these effects varied among groups. Our results suggest the need to consider the dynamics of land-use changes and the effects of past environments on the distributions of indicator taxa, otherwise we may misunderstand the effects of environmental degradation on biodiversity. (C) 2014 Elsevier Ltd. All rights reserved.
  • Nakamura Futoshi, Ishiyama Nobuo, Sueyoshi Masanao, Negishi Junjiro N, Akasaka Takumi
    RESTORATION ECOLOGY 22 (4) 544 - 554 1061-2971 2014/07 [Refereed][Not invited]
     
    The meanders and floodplains of the Kushiro River were restored in March 2011. A 1.6-km stretch of the straightened main channel was remeandered by reconnecting the cutoff former channel and backfilling the straightened reach, and a 2.4-km meander channel was restored. Additionally, flood levees were removed to promote river-floodplain interactions. There were four objectives of this restoration project: to restore the in-stream habitat for native fish and invertebrates; to restore floodplain vegetation by increasing flooding frequency and raising the groundwater table; to reduce sediment and nutrient loads in the core wetland areas; to restore a river-floodplain landscape typical to naturally meandering rivers. In this project, not only the natural landscape of a meandering river but also its function was successfully restored. The monitoring results indicated that these goals were likely achieved in the short term after the restoration. The abundance and species richness of fish and invertebrate species increased, most likely because the lentic species that formerly inhabited the cutoff channel remained in the backwater and deep pools created in the restored reach. In addition, lotic species immigrated from neighboring reaches. The removal of flood levees and backfilling of the formerly straightened reach were very effective in increasing the frequency of flooding over the floodplains and raising the water table. The wetland vegetation recovered rapidly 1 year after the completion of the meander restoration. Sediment-laden floodwater spread over the floodplain, and approximately 80-90% of the fine sediment carried by the water was filtered out by the wetland vegetation. © 2014 Society for Ecological Restoration.
  • Masanao Sueyoshi, Daisuke Nakano, Futoshi Nakamura
    FRESHWATER BIOLOGY 59 (2) 257 - 271 0046-5070 2014/02 [Refereed][Not invited]
     
    1. Flow refugia, characterised by low hydraulic stress during a flood, are key habitats that contribute to the persistence of benthic invertebrate. We investigated the use of different refugium types distributed across stream and floodplains and clarified which refugia contributed most to the persistence of assemblage and population during a seasonal snowmelt flood. 2. We sampled invertebrates and measured physical variables from six or nine types of channel units ('riffle', 'run ', 'lateral pool', 'backwater', 'abandoned pool' and 'tributary' at base flow, plus 'fast inundated area', 'slow inundated area' and 'side channel' at high flow) at four times (before, during, immediately after and after a flood). We analysed the use of refugia by assemblages, species with different ecological 'lifestyles' (a classification into different modes of mobility: burrower, climber, sprawler, clinger and swimmer) and populations. 3. Total density and species richness decreased significantly with flooding in riffles, runs and lateral pools. In contrast, total density and species richness did not change significantly in the other six types of channel units; therefore, these were distinguished as refugia. Among the six refugia, backwaters, tributaries and slow inundated areas had higher total densities than other refugia. The densities of the five lifestyles also decreased with flooding in riffles, runs and lateral pools. During flooding, high densities in backwaters and slow inundated areas were common for all lifestyles, whereas densities in other refugia varied with lifestyle. 4. The results for five common species showed that refugium use is species-dependent. The mayfly Paraleptophlebia japonica (Leptophlebiidae) and the cased caddisfly Neophylax ussuriensis (Uenoidae) were more numerous in refugia during flooding and recovered rapidly after flooding. In contrast, the mayfly Epeorus latifolium (Heptageniidae) and the net-spinning caddisfly Hydropsyche orientalis (Hydropsychidae) were rare in all types of channel units during and immediately after flooding. The cased caddisfly Allomyia delicatula (Apataniidae) was specific to tributaries and persisted throughout the research period. 5. Although some species did not use refugia effectively, various species with different mobility and ecological traits did persist and were found in refugia. Specifically, habitats with slowly flowing water that were spatially close to the main channel favoured the persistence of benthic invertebrates.
  • Soung Ryoul Ryu, Futoshi Nakamura
    Landscape and Ecological Engineering 10 (1) 201 - 202 1860-1871 2014/01 [Refereed]
  • YOSHII Chiaki, YAMAURA YUichi, SAGA Masashi, SHIBUYA Masato, NAKAMURA Futoshi
    Journal of Forest Research 20 (1) 167 - 174 1341-6979 2014 [Refereed][Not invited]
     
    We examined potentially contrasting conservation benefits of land sparing (land-use specialization) and land sharing (multiple-use forestry) strategies in forested landscapes by investigating relationships between bird functional group densities and basal areas of coniferous trees (an index of plantation intensity) in Sakhalin fir (Abies sachalinensis) and Sakhalin spruce (Picea glehnii) plantations. Densities of most bird functional groups increased with decreasing plantation intensity in both plantation types. In many cases, linear models were best for descriptors of bird density-plantation intensity relationships, but statistical support of linear and nonlinear (quadratic) models was similar. This outcome indicates that ecological benefits of land sparing and land sharing are potentially comparable in the plantations we studied. In real landscapes, land-use decision making depends on a variety of factors other than biodiversity conservation (e.g., social and biophysical factors). Furthermore, niche theory also predicts that population densities could linearly respond to environmental gradients. When density-intensity relationships are linear, as in this study, land-sparing and land-sharing strategies provide similar benefits in terms of biodiversity conservation, and contrasting land-use strategies could be flexibly chosen to enhance the accommodation of biodiversity conservation to resource production.
  • Matsubayashi J, Morimoto J, Mano T, Aryal A, Nakamura F
    Ursus 25 (2) 87 - 97 1537-6176 2014 [Refereed][Not invited]
     
    Interactions between brown bears (Ursus arctos) and anadromous salmon (Oncorhynchus spp.) constitute a unique energy pathway that facilitates nutrient cycling between marine and terrestrial ecosystems. Previous studies have documented variation in salmon consumption by brown bears; however, few have addressed potential anthropogenic factors influencing consumption. We assessed diet of brown bears on Hokkaido Island, Japan, using carbon and nitrogen stable isotopes to determine the effect of demographic (age and sex) and environmental (developed and undeveloped area) factors on salmon consumption. We collected thigh bones from 190 harvested bears from 1996 to 2011 and samples of their major dietary foods from 2009 to 2011, and we then estimated the potential contributions of these foods to the diets of brown bears using a Bayesian mixing model. Brown bears consumed more herbs, fruits, and corn than terrestrial animals or salmon at the population level. However, the dietary contribution of salmon varied widely among bears; in some cases, it comprised >30% of the total diet. Salmon consumption also varied by bear age class, sex, and location. Low salmon consumption by adult females with cubs suggested avoidance of salmon-spawning areas to minimize risk to their cubs. Bears inhabiting undeveloped areas were more likely to consume salmon than those inhabiting developed areas, suggesting that human activities restrict brown bears' salmon consumption. The lower salmon intake of Hokkaido brown bears compared with Alaskan brown bears may be attributed in part to extensive human development on Hokkaido Island, including in-stream structures that preclude salmon migrations and agricultural crops that provide an alternative food subsidy.
  • Yuya Toyoshima, Yuichi Yamaura, Yasushi Mitsuda, Yuki Yabuhara, Futoshi Nakamura
    FOREST ECOLOGY AND MANAGEMENT 307 54 - 62 0378-1127 2013/11 [Refereed]
     
    We examined the relationships between stand age and bird abundance in natural forests and two plantation types (larch Larix kaempferi and Todo fir Abies sachalinensis) in Tokachi district, northern Japan. Early successional species were found in 10-20-year-old larch and Todo fir plantations, as well as in older natural forests. The abundance of cavity nesters increased with stand age in all three forest types, but their abundance was consistently higher in natural forests than in plantations of the same age. We used these relationships to predict the abundance of each functional group under different forestry scenarios over a 100-year period. A scenario for optimizing larch plantations through a 100% replanting rate following clear-cuts (current replanting rate is 41%) maintained current harvest volumes over the next 100 years. One future possible scenario, in which the replanting rate was increased, resulted in higher wood production levels and a higher abundance of cavity nesters in larch plantations than the current trend scenario. Abandoned plantation clear-cuts were predicted to support large numbers of early successional species. The results also suggested that active wood production activities in natural forests would substantially decrease the abundance of cavity nesters in this region. (C) 2013 Elsevier B.V. All rights reserved.
  • Hideyuki Kawai, Nobuo Ishiyama, Koh Hasegawa, Futoshi Nakamura
    ECOLOGY OF FRESHWATER FISH 22 (4) 645 - 653 0906-6691 2013/10 [Refereed][Not invited]
     
    Flow regime is one of the major determinants of establishment success for non-native aquatic organisms. Here, we examine the influence of flow variability associated with snowmelt flood on the establishment success of non-native brown trout in 10 streams in northern Japan. We regarded the presence of Age-0 brown trout as the index of the successful establishment. The emergence of Age-0 brown trout in our study region begins in May, a time that overlaps with the occurrence of snowmelt flood. The presence of Age-0 brown trout was negatively associated with flow variability, and it was also negatively associated with summer water temperature. Our results indicate that the non-native brown trout tends to establish in the streams with smaller snowmelt floods and lower summer water temperatures. Brown trout is an invasive, non-native species that is problematic all over the world, and effective management strategies for preventing their further expansion are urgently needed. This study suggests that river managers should recognise that stable streams such as spring-fed streams (i.e., low flow and summer water temperature) and flow-regulated streams, have a higher potential risk of brown trout invasion.
  • Kikuchi Kokoro, Akasaka Takumi, Yamaura Yuichi, Nakamura Futoshi
    JOURNAL OF FOREST RESEARCH 18 (5) 389 - 397 1341-6979 2013/10 [Refereed][Not invited]
     
    The conservation of cavity trees in plantations is important for maintaining biodiversity because cavity trees are one of the forest attributes most strongly affected by forestry operations. We surveyed the occurrence of cavities at the tree-level and the abundance of cavity trees and the number of uses by secondary cavity users at the stand-level in natural and conifer plantation forests in Hokkaido, Japan. We classified cavities into two types by their formation processes: excavated and non-excavated. Excavated cavities were more common in dead trees than in live trees. Non-excavated cavities showed high occurrence in dead and live broad-leaved trees. The abundance of non-excavated cavity trees was two times greater than that of excavated cavity trees in natural forests, but, in plantations, excavated cavity trees were dominant. The abundance of non-excavated cavity trees was lower in thinned plantations than in not-thinned plantations. The number of cavity uses increased with the number of cavity trees, indicating the importance of maintaining cavity trees. Conifer plantations are established by removing native broad-leaved trees, which results in a lower abundance of non-excavated cavity trees in these locations. The conservation of broad-leaved trees is important for maintaining the current and future resource of non-excavated cavity trees in plantation forests, as is the conservation of dead trees, which showed a high occurrence of excavated cavities. © 2012 The Japanese Forest Society and Springer.
  • Yuya Toyoshima, Yuichi Yamaura, Yuki Yabuhara, Futoshi Nakamura
    JOURNAL OF FORESTRY RESEARCH 24 (3) 553 - 559 1007-662X 2013/09 [Refereed]
     
    In Japan, selective thinning is a common thinning method, though line thinning receives much attention because of its economic merits. In this study, we examined effects of the two thinning methods on bird communities in Todo fir (Abies sachalinensis) plantations in Hokkaido, Japan. We surveyed bird species in forests under four different management types - unthinned, selectively thinned, line-thinned plantation, and naturally regenerated forest (here after referred to as natural forest) stands - using a line-transect method. We also investigated vegetation structure (canopy tree and understory) of these stands. Bird species richness did not differ between natural forests and plantations, while bird total abundance was greater in plantations than in natural forests. Bird species richness and total abundance were comparable among the three management types for plantations. Abundances of 10 bird species were different among the four management types, and five species were more abundant in line-thinned plantations. However, two species were more abundant in selectively thinned stands than in line-thinned stands, and they frequently appeared in natural forests. There were no distinct differences in vegetation structure among the management types for plantations. Our results suggest that line thinning could be beneficial for some bird species in plantations.
  • 川の自然再生
    中村 太士
    国立公園 712 15 - 18 0466-3934 2013/04 [Not refereed][Not invited]
  • Toyoshima Yuya, Yamaura Yuichi, Mitsuda Yasushi, Yabuhara Yuki, Nakamura Futoshi
    The Japanese Forest Society Congress 日本森林学会 124 755 - 755 2013 
    森林の生物多様性は林齢に伴って変化する。従って、持続的な木材生産と共に、それぞれの遷移段階に依存した生物種を保全することが求められている。本研究では鳥類の林齢に沿った個体数変化をモデル化し、そのモデルを複数の木材生産性を持つ林業シナリオに適用することで、木材生産と鳥類多様性保全を両立する地域森林管理手法を探求することを目的とする。北海道十勝地域のカラマツ人工林、トドマツ人工林、天然林に若齢林から老齢林まで調査区を設置し、ラインセンサス法による鳥類調査を行った。観察された鳥類を遷移初期種、針葉樹選好種、樹洞営巣性種に分類し、各機能群の個体数と各林相の林齢の関係を一般化線形混合モデルによりモデル化した。続いて、十勝地域の今後100年間で想定される、複数の林業シナリオの下での齢級構成変化を予測し、構築したモデルを用いて各機能群の個体数変化を予測した。 解析の結果、カラマツ人工林の再造林率増加は、木材生産性と鳥類多様性の維持に大きく貢献できること、木質バイオマス燃料への需要増加などによる天然林の伐採量増加や人工林伐採跡地の天然更新率が、地域内の鳥類多様性に大きく影響することが示唆された。
  • Miho Morimoto, Junko Morimoto, Yoshiaki Moriya, Futoshi Nakamura
    Landscape and Ecological Engineering 9 (2) 259 - 270 1860-1871 2013 [Refereed][Not invited]
     
    Recently, the conversion of plantations into natural forests has attracted increasing attention, but little is known about how to convert a windthrown plantation into a natural forest. We examined the initial 3-year effects of salvage logging, site preparation, planting, and weeding in comparison with the effects of legacy retention after a typhoon blowdown on the changes in terrestrial environments and plant compositions and the similarity of the species composition to that of the intact natural forest. Our major findings are as follows: (1) A homogeneous, sunny, and flat environment continued for 3 years in the planted and weeded plot, whereas a heterogeneous environment was observed in the legacy retention plot; however, the light environment changed slightly in the planted plot. (2) The species composition in the planted plots changed greatly due to invasion by annual, biennial, and perennial herbs and early successional trees. Alien species also invaded the planted row. Conversely, the species composition changed little in the legacy retention, which was likely due to the presence of residual plants that prevented shade-intolerant species from being established. (3) The legacy retention, followed by the residual row, was the closest to the natural forest with respect to species composition, whereas the planted row was the most dissimilar from the natural forest. Legacy retention appears to be the most appropriate way to restore a natural forest immediately after a windthrow, yet supplemental planting may be necessary to restore the desired broadleaved species. © 2012 International Consortium of Landscape and Ecological Engineering and Springer Japan.
  • 中村 太士
    開発こうほう 北海道開発協会 (593) 14 - 19 2012/12 [Not refereed][Not invited]
  • 中村 太士
    科学 岩波書店 82 (11) 1241 - 1245 0022-7625 2012/11 [Refereed][Not invited]
  • 中村 太士
    ワイルドライフ・フォーラム 野生生物保護学会 17 (1) 16 - 16 1341-8785 2012/07 [Refereed][Not invited]
  • 中村 太士
    山林 大日本山林会 0 (1537) 2 - 11 0487-2150 2012/06 [Not refereed][Not invited]
  • Nobuo Ishiyama, Shigeya Nagayama, Takumi Akasaka, Futoshi Nakamura
    HYDROBIOLOGIA 686 (1) 257 - 266 0018-8158 2012/05 [Refereed][Not invited]
     
    The Japanese crayfish (Cambaroides japonicus), the only native crayfish in Japan, is endangered and has experienced rapid population declines. We surveyed the habitat requirements of Japanese crayfish at the reach and microhabitat scales in semi-natural low-gradient streams. Habitat use by Japanese crayfish differed between the spatial scales. Reach-scale analysis revealed that the bed slope was the only positive predictor of crayfish density. This finding indicates that relatively high-gradient reaches, such as headwater reaches, are an important habitat for the conservation of Japanese crayfish in low-gradient streams. Microhabitat-scale analysis showed that crayfish density was positively affected by substrate coarseness and the presence of instream vegetation cover (bank vegetation, woody debris, and leaf patches), whereas it was negatively affected by distance from the stream edge. Coarse substrates and vegetation cover may function as shelters from water flows and predators during low flow periods. The use of stream-edge areas may allow quick access to refugia and enable the crayfish to avoid unexpected flood disturbance and predation. These habitat characteristics should therefore be preserved for the conservation of Japanese crayfish, and scale-dependent habitat characteristics should be considered in future conservation plans.
  • Futoshi Nakamura, Nao Fuke, Mayumi Kubo
    PLANT ECOLOGY 213 (5) 735 - 747 1385-0237 2012/05 [Refereed][Not invited]
     
    The purpose of this study was to examine the effects of large wood (LW) on the physical environment and the initial establishment of vascular plant species in the Rekifune River, a large bar-braided monsoonal river in Japan. The physical environment and the diversity and composition of plant species were compared in relation to the orientation of LW pieces. We found that shading effects were more prevalent in the immediate vicinity of LW pieces than in quadrats distant from LW. The effect was especially strong at the center of LW jams (the "jam center"). Fine sand and silt were concentrated in the quadrats downstream from the LW pieces. In contrast, cobbles dominated the upstream quadrats. The highest diversity was found in the jam center, while intermediate values were observed in the quadrats surrounding LW. Indicator species analysis detected 21 indicator species only in the jam center. The LW jams favored the deposition of plant fragments and sediment and created shaded areas within and around the structures. Buried seeds may be transported with LW during a flood, and seeds dispersed by wind and stream flows may be trapped by the complex structure of LW jams. The specific environmental conditions and the trapping of seeds and plant fragments result in the early establishment of mid-successional tree species at LW jams. In conclusion, the LW pieces deposited on gravel bars altered the light and substrate conditions and thereby provided specific safe sites for various riparian plant species.
  • Yasunori Nakagawa, Takatoshi Nakamura, Hiroyuki Yamada, Futoshi Nakamura
    LIMNOLOGY 13 (1) 27 - 36 1439-8621 2012/04 [Refereed][Not invited]
     
    As part of the Kushiro Wetland Restoration Project, we evaluated the effect of the tree-cutting (February 2003) on soil water chemistry for 3 years in an alder (Alnus japonica) shrubland on the peat soil in the Kushiro Wetland, the largest wetland in Japan. The alder stand was divided into two types; low stature and high stature stands, mean heights being 1.5 and 2.6 m, respectively. The treatment plot with tree cutting and the reference plot measuring 25 m x 25 m each were established in both stands, and a soil incubation experiment was also conducted by trenching the root zone of wetland vegetation in the treatment plots in both stands in the summer of 2004. The tree cutting did not substantially increase the concentrations of ammonium ion (NH4 (+)) and nitrate ion (NO3 (-)) in the soil water, although a gradual and slight increase of NO3 (-) concentration was found after the tree-cutting only in the high stature stand (< 10 mu mol/l). This increase in the NO3 (-) concentration in the high stature stand was probably due to the rhizosphere oxidation of wetland herbaceous vegetation, and was accompanied by the increase of Ca2+ concentration. The soil incubation experiment showed no significant change of the nitrogen concentration, suggesting that inorganic nitrogen was immobilized and NO3 (-) was denitrified intensively in this wetland peat soil. The results of this study suggested that this wetland ecosystem had a high potential to stabilize the soil water chemistry.
  • Jung Il Seo, Futoshi Nakamura, Takumi Akasaka, Hidetaka Ichiyanagi, Kun Woo Chun
    WATER RESOURCES RESEARCH 48 (48) 0043-1397 2012/03 [Refereed][Not invited]
     
    We examined the relationships between large wood (LW) export and precipitation patterns and intensity by analyzing the data on the annual volume of LW removed from 42 reservoirs and the daily precipitation at or near the reservoir sites. We also calculated the effective precipitation by considering the antecedent precipitation. Both daily and effective precipitation data were used as explanatory variables to explain LW export. The model selection revealed that the precipitation pattern and intensity controlling LW export varied with latitude in the Japanese archipelago. In small watersheds with narrow channel widths and low discharges, mass movements, such as landslides and debris flows, are major factors in the production and transport of LW. In this case, the effective precipitation required to initiate mass movements regulated the LW export and did not vary with the latitude. In intermediate and large watersheds with wide channel widths and high stream discharges, heavy rainfall and subsequent floods regulated buoyant depth, influencing the initiation of LW movement. In southern and central Japan, intense rainfall accompanied by typhoons or localized torrential downpours causes geomorphic disturbances, which introduce abundant pieces of LW into the channels. However, these pieces continue to be removed by repeated rainfall events. Therefore, LW export is supply-limited and potentially produces less LW accumulation. Conversely, in northern Japan, where typhoons and torrential downpours are rare, LW export is transport-limited because LW pieces recruited by bank erosion, tree mortality, and windthrow accumulate and persist on valley floors. These pieces may be easily exported by infrequent flooding.
  • 中村 太士
    地質と調査 土木春秋社 2012 (1) 29 - 36 0913-0497 2012 [Not refereed][Not invited]
  • Takumi Akasaka, Munemitsu Akasaka, Futoshi Nakamura
    BIOLOGICAL CONSERVATION 145 (1) 15 - 23 0006-3207 2012/01 [Refereed][Not invited]
     
    Conserving biodiversity in agricultural landscapes is an urgent issue. The effective conservation of biodiversity requires plans based on species' habitat preferences at multiple spatial scales. We examined how the foraging habitat selection of bats varied with grain size (50,150,250, and 350 m)and how habitat selection in the home range differed from that in the foraging habitat in an agricultural landscape. Focusing on three sympatric Myotis species (Myotis petax, Myotis gracilis, and Myotis frater), we radio-tracked 10 individuals of each species for 121 nights in Hokkaido, northern Japan. Rivers and broadleaved riparian forests were commonly preferred at multiple scales, although the preferred land-cover type was dependent on both extent and grain size for most species. The best grain sizes for predicting the foraging-habitat use of M. petax and M. gracilis were 50 and 150 m. By contrast, M.frater showed no tendency across the grain sizes. Our results indicate that it is necessary to consider both extent and grain size to understand the habitat selection of bats. Our findings also suggest that focusing primarily on preferred land-cover types at multiple scales is effective for conservation planning, given the limited resources in terms of time, manpower, and finances. Although arable did not negatively affect the selection of foraging habitats and home ranges in these bat species, preventing the loss of rivers and forests should be prioritized over preventing arable land expansion. (c) 2011 Elsevier Ltd. All rights reserved.
  • Moriya Yoshiaki, Morimoto Miho, Morimoto Junko, Nakamura Futoshi
    JOURNAL OF THE JAPANESE FORESTRY SOCIETY THE JAPANESE FORESTRY SOCIETY 94 (1) 10 - 16 1349-8509 2012 [Refereed][Not invited]
     
    This study investigated the effects of salvage logging on deer browsing and the impact of browsing on vegetation in a windthrown conifer plantation forest. We compared browsing pressure among three treatments: "log", fallen logs retained; "planted", planting after salvaging; and "residual", residual rows with coarse woody debris that emerged after establishing planting rows. Then, we established a deer enclosure fence for each treatment. The results showed that browsing pressure was highest in the "planted" site, followed by the "residual" and "log" sites. This suggests that deer avoided places where fallen logs were left and that the arrangement of logs influenced browsing. Assessing the impact of browsing on the vegetation, we found increased herbaceous species richness outside the fence at the "planted" site and decreased vegetation height and herbaceous species richness outside the fence at the "residual" site. We did not find an impact of browsing on the vegetation at the "log" site. These changes may have been caused by differences in the species composition, height, and coverage of the vegetation among the treatments, by deer browsing, which decreased the volume of dominant plants, and by seed dispersal by deer. It was suggested that deer browsing can be decreased by keeping large fallen logs, although the effects of deer browsing on the vegetation were complicated and should be subject to long-term monitoring.
  • 中村太士
    河川 日本河川協会 10 (795) 3 - 5 0287-9859 2012 [Not refereed][Not invited]
  • Shigeya Nagayama, Futoshi Nakamura, Yoichi Kawaguchi, Daisuke Nakano
    HYDROBIOLOGIA 680 (1) 159 - 170 0018-8158 2012/01 [Refereed][Not invited]
     
    This study examined the effects of the configuration of wood structures on the use of local autumn and winter habitats by fish in a remeandering reach of a large lowland river. Fish diversity was higher at the simple wood-structure (SWS) and the log-jam (LJ) sites than at the no-wood (NW) sites during both seasons. In particular, the diversity at the LJ sites was higher than that at the SWS sites during the winter. The abundance of the four dominant fish species was generally higher at the LJ sites than at the NW sites during both seasons. The SWS and LJ sites were characterized by greater depths, finer bed materials, and more diverse flow conditions during the autumn. During the winter, the LJ sites were characterized by slower currents and finer bed materials. These habitat features satisfied the various habitat requirements of the fish observed in our study reach; during the autumn, areas with fast and slow currents were favorable for juvenile salmon, silt and sand bed materials for lamprey, and deep areas for one species of goby, while slow currents were critical in the winter for abovementioned fish species. Engineered log jams were also effective in supporting the colonization of fish during both seasons. These findings suggest that a larger and more complex wood structure, particularly log jams, plays important roles in creating local habitats suitable for various fish species during the autumn and winter and in preserving fish abundance and diversity in large lowland rivers.
  • YAMANAKA Satoshi, AKASAKA Takumi, NAKAMURA Futoshi
    Honyurui Kagaku (Mammalian Science) 日本哺乳類学会 51 (2) 265 - 275 0385-437X 2012 [Refereed][Not invited]
     
    To build a reference database of bat echolocation calls, we examined the regional variation in call structure (SF, EF, D, MF, and PF) of Myotis macrodactylus in Hokkaido, northern Japan. We recorded echolocation calls from an average of 41 individuals per site at seven sites (Urausu, Horokanai, Shintoku, Kamishihoro, Tsubetsu, Shiranuka, and Nanae; 290 individuals in total). Using these calls, we investigated the relationships among call structure, site and body size. The call structures of the bats did not differ among the sites. The body size of the bats showed differences among sites, but the call structures of the bats did not correlate with body size. Although we cannot neglect the possibility of migration between regions, we believe that our results are derived from the fact that the variation among individual bats exceeded the variation among sites. We concluded that a database of reference calls of Myotis macrodactylus in Hokkaido could be built without considering regional differences.
  • Yoshiaki Moriya, Miho Morimoto, Junko Morimoto, Nakamura Futoshi
    Nihon Ringakkai Shi/Journal of the Japanese Forestry Society 94 (1) 10 - 16 0021-485X 2012 [Refereed]
     
    This study investigated the effects of salvage logging on deer browsing and the impact of browsing on vegetation in a windthrown conifer plantation forest We compared browsing pressure among three treatments: "log", fallen logs retained; "planted", planting after salvaging; and "residual", residual rows with coarse woody debris that emerged after establishing planting rows. Then, we established a deer enclosure fence for each treatment The results showed that browsing pressure was highest in the "planted" site, followed by the "residual" and "log" sites. This suggests that deer avoided places where fallen logs were left and that the arrangement of logs influenced browsing. Assessing the impact of browsing on the vegetation, we found increased herbaceous species richness outside the fence at the "planted" site and decreased vegetation height and herbaceous species richness outside the fence at the "residual" site. We did not find an impact of browsing on the vegetation at the "log" site. These changes may have been caused by differences in the species composition, height, and coverage of the vegetation among the treatments, by deer browsing, which decreased the volume of dominant plants, and by seed dispersal by deer. It was suggested that deer browsing can be decreased by keeping large fallen logs, although the effects of deer browsing on the vegetation were complicated and should be subject to long-term monitoring.
  • 山下 慎吾, 根岸 淳二郎, 河口 洋一, 赤坂 卓美, 中村 知美, 島谷 幸宏, 中村 太士
    流域圏学会誌 流域圏学会 1 (1) 19 - 24 2186-9065 2012 [Refereed][Not invited]
  • Yuichiro Shida, Futoshi Nakamura
    PLANT ECOLOGY 212 (11) 1819 - 1829 1385-0237 2011/11 [Refereed][Not invited]
     
    In this article, we focused on hummocky microtopography as a prominent feature of mires and explored the microenvironmental conditions suitable for alder seedling establishment. Japanese alder (Alnus japonica) forest is widely distributed in wetlands in northern Japan. However, because alder seedlings are rare in mires, alder population dynamics and conditions that favor the establishment of alder seedlings are still unknown. The study was conducted in northern Japan at a site in mesotrophic mire. We surveyed the seedling density, the microenvironmental conditions (light, litter cover, and soil quality), and the density of dispersed seeds in alder forest and in the adjacent herbaceous fen. In addition, we performed a laboratory experiment to examine the germination characteristics of alder. Seedlings grew only on hummocks in alder forest. The percentage of litter cover on hummocks was lower than in hollows, and the density of dispersed seeds in alder forest was much higher than in herbaceous fen. Seeds of Japanese alder germinated under both light and dark conditions, and the germination rate were high under light and high-temperature conditions. Our results suggest that litter cover may inhibit seedling establishment and hummocks that characterized by less litter cover are suitable place for the establishment of seedlings. We conclude that hummocky microtopography and abundant seed rain in the mire enable the establishment of Japanese alder seedlings.
  • Koji Katagiri, Kazuo Yabe, Futoshi Nakamura, Yoshifumi Sakurai
    LIMNOLOGY 12 (2) 175 - 185 1439-8621 2011/08 [Refereed][Not invited]
     
    To identify the causes of the rapid expansion of the semi-emergent Phalaris arundinacea L. community in a nutrient-loaded river, we investigated the factors that determine the distribution of the Phalaris and other aquatic macrophyte communities and the shoot growth of P. arundinacea. The Phalaris community was distributed through areas with high organic nitrogen (Org-N), total phosphorus (T-P), PO(4)-P and suspended solids (SS) concentrations and low dissolved oxygen (DO). P. arundinacea shoots grow better in deep mud and high SS and T-P, all of which were strongly correlated with slower stream currents. Accordingly, although the concentration of total nitrogen constantly increased from 1985 to 1998, the determining nutrient for the expansion of the Phalaris community and P. arundinacea shoot growth stimulation was phosphorus rather than nitrogen. The Phalaris community increased rapidly between 1991 and 1996, when brief but prominent loadings of phosphorus were observed. We concluded that the Phalaris community was restricted due to phosphorus deficiency under nitrogen excess until 1991 and subsequently rapidly expanded over the channel due to the temporary excess phosphorus present during this period. Thereafter, the rapid expansion of the Phalaris community was maintained by the clogging effect of the floating mats formed by shoots and their remains of P. arundinacea, which results in slower currents. A slower current resulted in low DO, the sedimentation of degraded plant remains (high Org-N), and the adsorption of phosphorus by suspended matter (high SS and T-P). The anaerobic conditions caused by low oxygen and the accumulation of decomposable organic matter ensure the continuous development of the Phalaris community through the release of soluble phosphorus from the sediment.
  • Junko Morimoto, Miho Morimoto, Futoshi Nakamura
    FOREST ECOLOGY AND MANAGEMENT 261 (8) 1353 - 1361 0378-1127 2011/04 [Refereed][Not invited]
     
    All or a part of a sequence of forest practices (i.e., salvage logging, site preparation, planting crop trees, and weeding) has been implemented after natural disturbances for the rapid re-establishment of tree cover. Forest policies in Japan have recently changed from monocultural planting of coniferous crop trees to planting native broadleaved trees to restore forests and nurture local biodiversity following large windthrows. However, the effects of this new practice on preserving biodiversity, as well as the effects of legacy retention, have never been verified in Asia. Thus, the objective of our research was to compare the effects of legacy retention with plantation after salvaging on the initial stage of vegetation recovery in a blowdown area, specifically focusing on plant species diversity, the occurrence of alien species, and the composition of plant species. Following the analysis of our results, we finally describe appropriate practices to alter disturbed coniferous plantations to bring the species composition closer to that of the original natural mixed forests. A control (A, legacy retention) and three experimental treatment sites (B, salvage logged, site prepared, and Quercus crispula seedlings planted; C, same as B, but weeded once during the summer; and D, residual rows that emerged after establishing sites for planting) were prepared, and quadrats were set. Eleven indicators of the ground condition and the number of vascular plant species, including ferns, were quantified, and the number and abundance of residual and newly colonized plants of the main woody species were estimated. Our main findings were as follows: (1) in unsalvaged sites and residual rows, the diversity of plant species was poor, but a variety of plant species compositions were observed due to the heterogeneous conditions of the ground and ample residual plants; (2) in the planting site, many species appeared, but little variety of the species composition was observed due to the homogeneous condition of the ground and the destruction of residual plants; (3) a large number of alien species emerged in broad, unvegetated areas; (4) the impact of site preparation overwhelmed the impact of salvage logging on the initial recovery of plant species; and (5) to restore a natural mixed forest, a combination of legacy retention and plantation after salvaging would be the most appropriate. (C) 2011 Elsevier B.V. All rights reserved.
  • NAKAMURA Futoshi
    水利科学 日本治山治水協会 55 (322) 68 - 81 0039-4858 2011 [Not refereed][Not invited]
  • Mayumi Takahashi, Futoshi Nakamura
    LANDSCAPE AND ECOLOGICAL ENGINEERING 7 (1) 65 - 77 1860-1871 2011/01 [Refereed][Not invited]
     
    We examined the impacts of the Satsunai River Dam on the hydrology and development of riparian vegetation along the upper and lower reaches of the Satsunai River downstream from the dam. We estimated frequency curves of the flood discharge during the pre-dam (1976-1996) and post-dam (1997-2006) periods and simulated the flood frequency at sampling points within sites under pre-dam, post-dam and dam-removal (using the pre-dam flood discharge and post-dam cross-sections) scenarios. Changes in channel morphology and land cover were investigated by analyzing aerial photographs. Our results indicate that the 20-year flood at the upper site decreased substantially (from 599 to 271 m(3)/s) after dam operation, while that of the lower site decreased slightly (from 1025 to 977 m(3)/s). Within the upper site, the proportion of > 20-year return periods increased considerably (from 31.0 to 48.6%) while the proportion of 1- to 20-year return periods decreased (from 30.5 to 8.9%) after dam operation. Flood frequency results for the dam-removal scenario were similar to those for the pre-dam period, suggesting that a return to pre-dam discharge rates would restore the pre-dam distribution of flood frequency at the upper site. Within the lower site, however, the distribution of flood frequency varied little between the pre- and post-dam scenarios, because tributary inflows between the sites mitigated the impacts of dam-regulated flows. Land cover types were associated with flood frequency at both sites. The reduced flood frequency of the upper site resulted in increased area of riparian vegetation and decreased area of active channel.
  • Toyoshima Yuya, Yamaura Yuichi, Mitsuda Yasushi, Yabuhara Yuki, Nakamura Futoshi
    The Japanese Forest Society Congress 日本森林学会 123 Pb168 - Pb168 2011
  • Mayumi Takahashi, Futoshi Nakamura
    Landscape and Ecological Engineering 7 (1) 79 - 79 1860-1871 2011/01 [Refereed][Not invited]
  • Jung Il Seo, Futoshi Nakamura, Kun Woo Chun
    LANDSCAPE AND ECOLOGICAL ENGINEERING 6 (2) 271 - 287 1860-1871 2010/07 [Refereed][Not invited]
     
    Recent research has elucidated the positive ecological roles of large wood (LW) in fish-bearing channels. However, where logjams increase local flooding and bank erosion, LW has negative impacts on public safety and property protection. Although our understanding of reach-scale processes and patterns has increased dramatically in recent years, only a few studies have integrated this knowledge at the watershed scale. Here we review variations in LW dynamics along a gradient of watershed sizes. In small watersheds, a massive amount of LW, resulting from forest dynamics and hillslope processes, remains on the valley floor. These pieces may persist for several decades and are eventually transported during debris flows. In intermediate watersheds, LW is dominantly recruited by bank erosion from adjacent riparian areas. These pieces are continuously transported downstream with LW pieces that are supplied from the upstream watershed by floods because these channels have a greater width and depth than the length and diameter of the pieces, as well as a high stream power. This leads to fragmentation of the LW pieces, which increases their transportability. In large watersheds, LW pieces are frequently recruited at locations where the channel is adjacent to riparian forests. Floated LW pieces can accumulate along channels with wide floodplains. Storage in floodplains can lead to more rapid decay than in an anaerobic environment, resulting in the subsequent removal of LW pieces from the system. Our review presents a generalized view of LW processing at the watershed scale, and is relevant to ecosystem management, disaster prevention and the identification of knowledge gaps.
  • Shigeya Nagayama, Futoshi Nakamura
    LANDSCAPE AND ECOLOGICAL ENGINEERING 6 (2) 289 - 305 1860-1871 2010/07 [Refereed][Not invited]
     
    To provide river managers and researchers with practical knowledge about fish rehabilitation, various studies of fish habitat rehabilitation that used wood were reviewed. The review focuses on fish responses, wood installation methods, and geomorphic features of the rehabilitation sites. Most studies were conducted in moderately sized (small and medium) streams with relatively high bed gradients and aimed to improve the habitats of salmonid species. In this stream type, structures spanning the full (log dam) and partial (log deflector) width of the river were most common, and wood structures that created pools and covers were successful in improving fish habitat. Some projects were conducted in moderately sized low-gradient streams, in which wooden devices used to create instream cover were effective for fish assemblages. There were few studies in other aquatic ecosystems. However, well-designed large wood structures, known as engineered log jams, were used in rehabilitation projects for large rivers. In slack-water or lentic systems such as side-channels, estuaries, and reservoirs, small and large wood structures that created cover were used to improve habitat for many fish species. For successful fish habitat rehabilitation projects, the hydrogeomorphic conditions of rehabilitation sites should be carefully examined to avoid physical failure of wood structures. Although artificial wood structures can be used to improve fish habitat in various aquatic ecosystems, they should be considered to be a complementary or interim habitat enhancement technique. The recovery of natural dynamic processes at the watershed scale is the ultimate target of restoration programs.
  • Alexander K. Fremier, Jung Il Seo, Futoshi Nakamura
    GEOMORPHOLOGY 117 (1-2) 33 - 43 0169-555X 2010/04 [Refereed][Not invited]
     
    Large wood maintains in-channel and floodplain habitats by influencing the biophysical character of the river corridor. Large wood dynamics in a river corridor are a product of watershed wide processes and also of local recruitment, transport, and storage. This complexity of scales added to the logistical constraints in taking measurements limits our understanding of large wood dynamics through the watershed. To begin to unravel this issue, we compiled a data set of the volume of large wood deposited annually into 131 reservoirs across Japan and compared large wood export to flow discharge and watershed characteristics (watershed size, latitude, channel slope, percent forest, and forest type). We found that large wood was predominately transported during peak flow events. Large wood export increased logarithmically with watershed area. The decreasing export rate of large wood per watershed area is interpreted as a combination of annual export variability in upper watersheds, a non-significant increase in large wood recruitment along the longitudinal gradient (potentially human influenced), the increase in long-term storage on adjacent large floodplains, and significant decay/fragmentation downstream. Watersheds<10-20 km(2) had a highly variable large wood export pattern, conforming generally to previously published work that suggest transport limitation in smaller watersheds. The data suggest the existence of an export threshold (similar to 75 km(2)) where large wood export is no longer related to watershed size. Export across all watershed sizes was controlled by watershed characteristics (slope, percent forested, etc.) and peak discharge events. The connection with upstream watersheds and laterally with the floodplain increases the net flux of large wood through downstream transport and retransport of buried logs. Identifying rates of large wood transport from watershed connectivity as a potential key input process will improve our basic understanding of geomorphic and ecological patterns within the watershed. These results highlight the importance of understanding the local-and watershed-scale dynamics of large wood in creating and maintaining more heterogeneous riparian and aquatic habitat along the river corridor. Published by Elsevier B.V.
  • 標津川における河川生態学術研究の取り組みと成果
    中村太士, 小川豪司
    RIVERFRONT (69) 2 - 5 2010 [Not refereed][Not invited]
  • 釧路川そして釧路湿原の再生−これまでの進展と今後の課題−
    中村太士
    FRONT MOOK (5) 48 - 51 2010 [Not refereed][Not invited]
  • 河川生態系を蘇らせる新たな視点.
    中村太士
    河川 3 (776) 11 - 17 2010 [Not refereed][Not invited]
  • 人口減少社会における防災と自然環境の保全.
    中村太士
    月刊建設 9 (55) 4 - 5 2010 [Refereed][Not invited]
  • Futoshi Nakamura, Eishige Komiyama
    LANDSCAPE AND ECOLOGICAL ENGINEERING 6 (1) 143 - 152 1860-1871 2010/01 [Refereed][Not invited]
     
    The Shiretoko Peninsula was placed on the World Heritage List in July 2005 as Japan's third Natural Heritage Site, being valued for its unique ecosystems formed by the interaction between marine and terrestrial environments. Prior to its listing, however, the International Union for Conservation of Nature and Natural Resources requested the development of measures to allow for the free movement of salmonids through the nominated area via artificial in-stream structures. This report introduces a pioneering effort to modify check dams in order to improve ecosystem linkages. The River Construction Working Group has intensively discussed and implemented restoration projects for 3 years, and the results have been monitored after implementation. Of 44 streams within the Shiretoko World Natural Heritage Site, 14 streams have had one or more in-stream structure(s) built. A total of 123 structures, mainly soil conservation dams, are distributed sporadically in these streams. Following assessment, the Working Group concluded that it would be reasonable to modify 31 structures in five streams, including 18 structures that were to be modified before listing. The most suitable design that met local stream conditions was selected, after accounting for salmon passage, adverse impacts on stream environments above and below the construction sites and on fishing grounds, efficiency of construction, and ease of postmodification maintenance. Working in cooperation with the group members and parties concerned, we succeeded in restoring salmonids' upstream runs and extending their spawning habitat in streams above some of the dams, while keeping the disaster prevention function of the dams intact.
  • 中村太士
    Environmental research quarterly 日立環境財団 (158) 120 - 128 0285-9769 2010 [Refereed][Not invited]
  • 中村 太士
    水文・水資源学会誌 23 (1) 1 - 2 0915-1389 2010/01 [Refereed][Not invited]
  • Nobuhisa Nagami, Kazuo Yabe, Futoshi Nakamura
    JAPANESE JOURNAL OF CONSERVATION ECOLOGY 15 (1) 29 - 38 1342-4327 2010 [Refereed][Not invited]
     
    We investigated the fen communities and their hydrochemical environments in Abiragawa, which embraced the largest area of fens in Yufutsu district, and compared with communities growing in neighboring seven mires. Three groups were identified; Group A (Calamagrostis langsdorffii) predominantly occurred in floodplain mires and Group C (Carex lasipcarpa var. occultons) in valley mires. Two types of Group B dominated by Thelypteris palustris occurred exclusively in lower water level areas of Abiragawa. B1 had mixed species composition with Group A, and B2 with Group C. The EC and pH values in B2 were lower than B1. After the modification of river course in 1956, water supply to Abiragawa had interrupted. In Abiragawa, Group A is growing and one type of Group C was described on 1975. The dominance of Thelypteris, which grows in drier habitats indicates that the hydrological change could develop the communities of Group B by deteriorating the communities of Group A and C. The alder forest (Alnus japónica) has increased by 50% for the last 29 years and replaced fens, provably owing to hydrological changes. Accordingly, recovering the hydrological conditions before modifying rivers would be effective to restore fen communities in Abiragawa.
  • Young Sang Ahn, Futoshi Nakamura, Kun Woo Chun
    GEOMORPHOLOGY 114 (3) 284 - 293 0169-555X 2010/01 [Refereed][Not invited]
     
    Sediment dynamics for the last 300 years in Lake Toro and the applicability of Pb-210 dating (CIC and CRS models) are evaluated. The lake sedimentation and sediment yield were determined by Cs-137 (in 1963) and two tephra layers (Ko-c2 in 1694 and Ta-a in 1739). The average sediment yields for initial development periods of catchments were 13.0-14.1 t km(-2) yr(-1) until 1963 and increased to 30.5 t km(-2) yr(-1) after 1963 because of the conversion of floodplain and upland forests to cultivated lands. In particular, the western zone of the lake near the conjunction with the Kushiro River had a high sedimentation rate, which is attributable to sediment inflow back from the Kushiro River during floods. The CIC model was not applicable because of fluctuations in the Pb-210 profiles since 1963. The CRS model agrees with the Cs-137 dating in all sites except for one site close to the Kushiro River inflow. Pb-210 dating may contain considerable errors where the Pb-210 concentration profile and flux are perturbed by floodwater from the Kushiro River, which contains low levels of Pb-210. (C) 2009 Elsevier B.V. All rights reserved.
  • Masao Himura, Koji Nishi, Futoshi Nakamura, Kiwamu Kawaguchi, Takaaki Torit, Yoko Takeuchi, Masatoshi Nishikawa, Hitomi Godo, Shinichiro Tate, Yasusuke Kurosaki, Marie Murakami
    Ecology and Civil Engineering 応用生態工学会 13 (1) 9 - 23 1882-5974 2010 [Refereed][Not invited]
     
    The purpose of this study is to verify the validity of the habitat assessment based on physical environments using biological community data in middle reaches of the Shibetsu River, eastern Hokkaido, Japan. We surveyed biological assemblages (fish, benthic invertebrates, terrestrial plants and birds) at 16 sites in the study reaches and examined relationships between the physical assessment results (DDR: the degree of departure in physical conditions from reference sites) and biological data: 1) abundance or diversity of species that are typical in pristine environment of the study reaches and 2) community compositions. The community compositions were analyzed by the Detrended Correspondence Analysis (DCA) ordination. Abundances of the typical fish and plant species were high in the sites that were evaluated as ‘good’ by the physical habitat assessment, whereas they were low in those as ‘degraded’. The first axis of DCA showed a gradient in species composition reflecting anthropogenic influences and correlated with DDR and many physical variables in fish, benthic invertebrate and terrestrial plant communities. The main DCA axes showed no relationship with DDR and few relationships with physical variables in bird communities. Our results showed that the habitat assessment method using the degree of departure in physical conditions from reference sites was an effective tool for comprehensive river habitat assessment. © 2010, Ecology and Civil Engineering Society. All rights reserved.
  • Hisashi Miya, Toshiya Yoshida, Mahoko Noguchi, Futoshi Nakamura
    JOURNAL OF FOREST RESEARCH 14 (5) 302 - 310 1341-6979 2009/10 [Refereed][Not invited]
     
    We analyzed temporal patterns in diameter growth of saplings following selection harvesting in an uneven-aged mixed stand dominated by Abies sachalinensis, Acer mono, Quercus crispula, and Betula ermanii in Hokkaido, northern Japan. We examined interspecific differences in growth responses to local growing conditions including harvesting intensity, crowding, stem size, and past duration of the small growth period. Consistent with expectations based on shade tolerance of the species, the age at which the individual reached a diameter at breast height (DBH) of 12.5 cm was highest for A. sachalinensis and lowest for B. ermanii. The interspecific growth differences between saplings that had or had not experienced local harvesting increased gradually for A. sachalinensis and B. ermanii, but peaked at around 4-6 years after harvesting for Q. crispula. Generalized linear mixed model analysis clearly suggested that individual growth conditions required to enhance diameter growth of saplings differed considerably among species. For Q. crispula and B. ermanii, local harvesting intensity was most strongly and positively associated with diameter growth rate, whereas for A. sachalinensis and A. mono, stem size had the strongest negative effect. Abies sachalinensis saplings responded more to surrounding harvesting when they were relatively small, whereas A. mono showed a weak opposite response. The duration of the small growth period before harvesting had negative effect for A. sachalinensis, but not for the other species. Our study indicated that the influence of selection harvesting on growth of shade-tolerant species depends upon pre- and post-harvest growing conditions.
  • Young Sang Ahn, Futoshi Nakamura, Toshikazu Kizuka, Yugo Nakamura
    EARTH SURFACE PROCESSES AND LANDFORMS 34 (12) 1650 - 1660 0197-9337 2009/09 [Refereed][Not invited]
     
    The purpose of this study was to examine the historical change in sedimentation rates in lakes that have been impacted by river regulation and agricultural activities in the Ishikari River floodplain. We dated sediment cores using caesium-137 (Cs-137) dating and tephrochronology, and we estimated sediment sources from Cs-137 concentrations in the topsoil of representative land covers. We found that, between 1739 and 1963, the distance between the lake and the main river channel and whether or not the lake was connected to the river affected the sedimentation rates. After 1963, agricultural drainage systems were established in the Ishikari River floodplain. The average sedimentation rate before and after the construction of drainage ditches varied between 1-66 and 87-301 mg cm(-2) a(-1), respectively. The increase in the sedimentation rate after 1963 was caused by the construction of a number of drainage networks, as well as extensive cultivation activity and/or fragmentation of the swamp buffers surrounding the lakes. The Cs-137 activities at the surfaces of the lake as well as the catchment-derived Cs-137 contributions and Cs-137 inventory in the lake profiles were used to examine the sediment influx from the various drainage areas after the establishment of the drainage system. Our results indicate that the majority of the lake sediments were derived from cultivated areas, and therefore the catchment-derived Cs-137 contribution in the lakes was strongly correlated with the sedimentation rate. The Cs-137 inventory across all of the lake profiles was also significantly greater than the atmospheric fallout. We identified a negative correlation between the Cs-137 lake profile inventory and the sedimentation rate. This is because the sediment originating from the drainage areas contained low Cs-137 concentrations, which diluted the overall concentration of Cs-137 in the lake sediment. Copyright (C) 2009 John Wiley & Sons, Ltd.
  • Yuichiro Shida, Futoshi Nakamura, Hiroyuki Yamada, Takatoshi Nakamura, Nobuhiko Yoshimura, Masami Kaneko
    WETLANDS 29 (3) 988 - 996 0277-5212 2009/09 [Refereed][Not invited]
     
    We examined factors that influence the expansion of alder forests in a wetland isolated by dikes and drainage ditches in northern Japan. Using aerial photographs, airborne laser scanner data, and existing elevation data, we described the spatial distribution and heights of alder forest in 2002 and the spatial distribution in 1977. We also measured water level and water quality in 2002. The mean water level was slightly lower than the ground surface, and water level fluctuation was minimal. The study site was mesotrophic, but salt concentration was high. The alder forest expanded around the area adjacent to the alder forests present in 1977, and the canopy cover ratio increased over a wide area. A generalized linear model suggested that water level and quality and the previous distribution of reproductively mature trees controlled the expansion pattern of the alder forest. A decrease in water level fluctuation promoted initial establishment, while an increase in fluctuation promoted height growth. A decrease in salt concentration or acidity promoted both initial establishment and growth. Flood protection by dikes may change spatial distribution of alder trees by narrowing water level fluctuation, restricting fruit dispersal, and reducing tree mortality.
  • Takumi Akasaka, Daisuke Nakano, Futoshi Nakamura
    BIOLOGICAL CONSERVATION 142 (7) 1302 - 1310 0006-3207 2009/07 [Refereed][Not invited]
     
    To conserve the foraging habitat of Daubenton's bat (Myotis daubentonii) in a large lowland river, we investigated the influence on this bat of prey variables (number or biomass) and insect origin (aquatic or terrestrial). We tested the hypothesis that river restoration (re-meandering) conducted in the Shibetsu River, northern Japan, enhances foraging habitat quality by increasing the abundance of aquatic insects. From June to September 2004, flying insects were collected using Malaise traps in restored and channelised reaches in the Shibetsu River. Bat activity was recorded by bat detectors placed near the Malaise traps in each of the two reaches. Foraging activity of Daubenton's bat was more strongly related to the number of insects than to biomass, and to adult aquatic insects than to terrestrial insects. The high dependence of Daubenton's bat on aquatic prey was attributed to the fact that aquatic insect numbers were always higher than those of terrestrial insects. Contrary to the hypothesis, Daubenton's bat was more active in the channelised reach than the restored reach in all months except June, and it synchronized its foraging activity with the seasonal distribution of adult aquatic insects. However, the study was undertaken just two years after restoration and the riparian vegetation had not yet established itself Our results demonstrate the importance of aquatic insect abundance for Daubenton's bat throughout the seasons in large lowland rivers. A further decrease in aquatic insects, associated with progressive anthropogenic alteration of river environments, undoubtedly exerts a harmful influence on the conservation of this species. (C) 2009 Elsevier Ltd. All rights reserved.
  • Hiroyuki Yamada, Futoshi Nakamura
    LANDSCAPE AND ECOLOGICAL ENGINEERING 5 (2) 169 - 181 1860-1871 2009/07 [Refereed][Not invited]
     
    In recent years, fine sediment, produced by run-off associated with forestry activity and agricultural development that accumulates on riverbeds, has exerted a deleterious influence on lotic ecosystems. This study examined the Oroennukibetsu River, a tributary of the Nukibetsu River, which has been affected by high loads of suspended sediments. Effects of accumulation of fine sediment on the survival rate of masu salmon embryo and also on the redd environment (permeability and intragravel dissolved oxygen concentration) were quantified through a field experiment. Results show that the interchange of DO between intragravel and surface water was not affected directly by permeability or the accumulated fine sediment and that intragravel flow rates can be an important factor controlling embryo survival. A decrease in permeability associated with accumulation of fine sediment lowered the survival rate of embryos by suffocation because the flux of DO that should be supplied to the embryo was severely limited. This situation might be created by the combined effects of an accumulation of fine sediment on the redd and a low DO concentration in the surface water because the DO concentration almost coincided with the intragravel DO.
  • ISHIYAMA Nobuo, WATANABE Keizo, NAGAYAMA Shigeya, NAKAMURA Futoshi, KENMOTSU Hirotaka, TAKAHASHI Hiroki, MARUOKA Noboru, IWASE Haruo
    Ecology and civil engineering 応用生態工学会 12 (1) 57 - 66 1344-3755 2009/07 [Refereed][Not invited]
  • Jung Il Seo, Futoshi Nakamura
    EARTH SURFACE PROCESSES AND LANDFORMS 34 (6) 786 - 800 0197-9337 2009/05 [Refereed][Not invited]
     
    The annual fluvial export of large wood (LW) was monitored by local reservoir management offices in Japan. LW export per unit watershed area was relatively high in small watersheds, peaked in intermediate watersheds, and decreased in large watersheds. To explain these variations, we surveyed the amount of LW with respect to channel morphology in 78 segments (26 segments in each size class) in the Nukabira River, northern Japan. We examined the differences in LW dynamics, including its recruitment, transport, storage, and fragmentation and decay along the spectrum of watershed sizes. We found that a large proportion of LW produced by forest dynamics and hillslope processes was retained because of the narrower valley floors and lower stream power in small watersheds. The retained LW pieces may eventually be exported during debris flows. In intermediate watersheds, the volume of LW derived from hillslopes decreased substantially with reductions in the proportion of channel length bordered by hillslope margins, which potentially deliver large quantities of LW. Because these channels have lower wood piece length to channel width ratios and higher stream power, LW pieces can be transported downstream. During transport, LW pieces are further fragmented and can be more easily transported. Therefore, the fluvial export of LW is maximized in intermediate watersheds. Rivers in large watersheds, where the recruitment of LW is limited by the decreasing hillslope margins, cannot transport LW pieces because of their low stream power, and thus LW pieces accumulate at various storage sites. Although these stored LW pieces can be refloated and transported by subsequent flood events, they may also become trapped by obstacles such as logjams and standing trees on floodplains and in secondary channels, remaining there for decades and eventually decaying into fine organic particles. Thus, the fluvial export of LW pieces is low in large watersheds. Copyright (C) 2009 John Wiley & Sons, Ltd.
  • 永山滋也, 河口洋一, 中野大助, 中村太士
    寒地土木研究所 土木研究所寒地土木研究所 (673) 31 - 35 1881-0497 2009 [Refereed][Not invited]
  • Morimoto Junko, Takei Naoko, Sato Hirokazu, Kaneko Masami, Nakamura Futoshi
    Bulletion of the International Association for Landscape Ecology-Japan Japan Association for Landscape Ecology 13 (1) 2,113-121 - 121 1880-0092 2009 [Refereed][Not invited]
     
    Controls of floods and water quality are of great concern in Shiraoi town, Hokkaido. The function of soil and water conservation in three sub-watersheds in the town was evaluated and its reliability was tested. The methods to evaluate forest function, which was developed by Hokkaido prefecture government, are easy to employ, and the results are easy to understand for local people, and therefore we used them. The chronological changes in those functions were compared among three sub-watersheds in the following three years. They are 1948 representing the period of postwar rehabilitation, 1976 being post rapid growth period in Japanese economy, and 2006, the period after the collapse of bubble economy. Agreements of the scores and vegetation changes due to the change of social situation were examined. In results, 1) function of soil and water conservation were degraded temporarily after clear-cutting, 2) conversion of land use to the quarries caused a decline in the function of soil and water conservation, which may continue for a long time, 3) function of mitigating drought and flood was most sensitively affected by forest exploitation, 4) function of controlling water quality greatly declined when riparian zone having steep slopes was broadly developed. The scores were mostly explained by vegetation changes due to the change of social situation. While comparing scores of other sub-watersheds pointed out problems to be solved. It is necessary to simplify the evaluation procedure and show standards of judgment with regard to scores to make the guideline more lucid one.
  • Shigeya Nagayama, Yoichi Kawaguchi, Daisuke Nakano, Futoshi Nakamura
    CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES 66 (1) 42 - 51 0706-652X 2009/01 [Refereed][Not invited]
     
    Different size classes of masu salmon (Oncorhynchus masou) were partitioned in three-dimensional space in habitats created by artificially installed large wood (LW) structures in a large river. Fish >300 mm in size (L-sized) returning from the ocean distinctly occurred in sheltered areas near the riverbed, which had a moderate current velocity and contained large root wads or tree trunks; 140-200 mm (M-sized) and 100-120 mm (S-sized) fish selected deep areas of high velocity current adjacent to LW structures; <= 80 mm fish (SS-sized) were most common in the lower depth layers throughout all LW habitats, including shallow areas with moderate currents where LW structures blocked the fast currents. Some SS-sized fish used cover areas provided by branches and leaves. Masu salmon abundance in all size classes combined was greater in habitats with LW structures than in habitats without them. Our study suggests that the natural recruitment of whole trees from the riparian zone or artificial placement of whole trees will have a profound effect on creating salmonid habitats in large rivers.
  • MURAKAMI Marie, KUROSAKI Yasusuke, NAKAMURA Futoshi, GODO Hitomi, TATE Shinichiro, NISHI Koji, HIMURA Masao
    Ecology and civil engineering 応用生態工学会 11 (2) 133 - 152 1344-3755 2008/12 [Refereed][Not invited]
     
    The purpose of this study is to conduct a simple and comprehensive stream assessment based on a "Degree of Departure from Reference (DDR)" in physical environments. We define 'departure' as the distance between a reference site and each test site in multiple principal component dimensions of physical conditions. The assessment was conducted at the reach scale. The three categories were anthropogenic alteration, habitat diversity and stream & floodplain structure, with each consisting of specific indices representing physical conditions of the stream and floodplain. We established 68 test sites in a lowland, valley bottom segment of the Shibetsu River, Hokkaido, northern Japan, where relatively undisturbed reference sites were available. Physical conditions for each reach were measured, using a survey method modified from the River Habitat Survey, a quantitative assessment system that has been developed and practiced in the United Kingdom. The test sites were classified into principal components separately for three categories. A group of least disturbed sites was determined as a reference. The departure in physical conditions was smallest within the reference group and was large in other reaches which exhibited differences from the reference group in terms of multiple indices. These sites departing from the reference flow through urban areas and show a high level of alteration, low habitat divesity and sinuosity and less frequent occurrence of riffles, pools and bars. The Degree of Departure from Reference is an objective measurement of differences between reference conditions and a target site for assessment, which provides a comprehensive, accurate evaluation of stream physical environments. Our assessment method is applicable to other rivers. It can be also more easily used for spatially large-scale assessment relative to the ones with biotic indices, thereby providing an effective tool for 'mass-screening test' of river environments.
  • Young Sang Ahn, Futoshi Nakamura, Shigeru Mizugaki
    ENVIRONMENTAL MONITORING AND ASSESSMENT 145 (1-3) 267 - 281 0167-6369 2008/10 [Refereed][Not invited]
     
    Suspended sediment and nutrient loadings from agricultural watersheds have lead to habitat degradation in Lake Takkobu. To examine their relationships with land-use activities, we monitored sediment, nutrient and water discharges into the lake for a 1-year sampling period. The Takkobu River contributed the largest portion of the annual water discharge into the lake, compared with the other tributaries. During dry conditions, lake water flowed into the Kushiro River, and conversely during flooding, Kushiro River water flowed into the lake. Inflows from the Kushiro River had a high proportion of inorganic matter, with high concentrations of total nitrogen and total phosphorus, attributed to agricultural land-use development and stream channelization practiced since the 1960s in the Kushiro Mire. Nutrient loadings from these two rivers were significantly higher during flooding than in dry conditions. However, there was no clear correlation between river discharge and nutrient concentrations. Since land-use activities in the Kushiro River and Takkobu River watersheds were concentrated near rivers, nutrients easily entered the drainage system under low flow conditions. In contrast, water discharged from small, forest-dominated watersheds contained a low proportion of inorganic matter, and low nutrient concentrations. The suspended sediment delivered to the lake during the sample period was estimated as approximately 607 tons, while the total nitrogen and total phosphorus inflows were about 10,466 and 1,433 kg, respectively. Suspended sediment input into the lake was 65%, and total nitrogen and total phosphorus were 40% and 48%, respectively, being delivered by the Kushiro River.
  • Hiroyuki Yamada, Futoshi Nakamura, Yasuharu Watanabe, Marie Murakami, Takeshi Nogami
    Hydrological Processes 22 (17) 3545 - 2524 0885-6087 2008/08/15 [Refereed][Not invited]
  • TACHIKI Yasuyuki, YOSHIMURA Tetsuhiko, HASEGAWA Hisashi, SAKAI Tetsuro, NAKAMURA Futoshi
    Journal of the Japan Forest Engineering Society 森林利用学会 23 (2) 41 - 52 1342-3134 2008/08 [Refereed][Not invited]
     
    In 1999, the Forestry Agency of Japan launched a new nation-wide forest resources monitoring project. We developed "DeltaForest: a navigation system for the forest resources monitoring project" using a Personal Digital Assistant (PDA) and the Global Positioning System (GPS). The DeltaForest consists of two components: DeltaTracer and DeltaMapper. The DeltaTracer works on a PDA with a GPS receiver, and navigates the user to the destination point, tracing the route recommended by the predecessor, while the DeltaMapper works on a desktop computer and facilitates the work of editing and storing...
  • Yuri Kumagai, Young Sang Ahn, Futoshi Nakamura
    JOURNAL OF FOREST RESEARCH 13 (4) 223 - 232 1341-6979 2008/08 [Refereed][Not invited]
     
    The vegetation of Takkobu, northern Japan, has been significantly altered by land-use development following Japanese settlement at the end of the 19th century. In order to assess the impact of human activity on vegetation dynamics in Takkobu, changes in the vegetation composition over the last 300 years were reconstructed from fossil pollen in the sediments of Lake Takkobu. The pollen assemblage represented broadleaved forests on the surrounding hills and alder forests found on the margin of the wetland bordering the lake. Prior to Japanese settlement, the hillside forests consisted predominantly of oak. However, with the onset of land-use development, a significant decline in oak relative to increasing birch was apparent, particularly after the early 1960s. These results suggest that successive logging since the 1880s had gradually undermined the resilience of oak. An increase of Artemisia and birch pollen also indicates an expansion of disturbed land. Since the 1960s, a large part of the broadleaved forests in Takkobu has been converted to larch plantations, although this was not represented in the pollen data because of the underrepresentation of larch pollen. The results of the pollen analysis have implications for forest restoration in Takkobu. The use of long-term data allows the determination of the baseline (natural) vegetation to be restored, and also illustrates the factors affecting present-day vegetation and how it may change in the future.
  • Daisuke Nakano, Futoshi Nakamura
    AQUATIC CONSERVATION-MARINE AND FRESHWATER ECOSYSTEMS 18 (5) 780 - 798 1052-7613 2008/07 [Refereed][Not invited]
     
    1. Many rivers and streams across the world have been channelized for various purposes. Channel cross-sections of meandering rivers are asymmetrical and have cross-sectional diversity in their physical environment; cross-sections of a channelized river are typically trapezoidal and have little cross-sectional diversity, both in physical and ecological conditions. Several programmes to restore stream meanders have been undertaken to improve river ecosystems degraded by channelization. However, the association between diversification in the physical environment due to meander restoration and the macroinvertebrate community structure is poorly known. 2. This study of a lowland river in Japan assessed how the cross-sectional diversity of the physical environment changed with restoration of a meander in a channelized river, and how the macroinvertebrate communities responded to the changes in physical habitat variation. Comparisons were made between the macroinvertebrate communities of a channelized reach, the restored meandering reach, and a natural meandering reach. 3. Natural meandering and restored meandering reaches showed higher cross-sectional diversity in physical variables and total taxon richness across a reach than did the channelized reach. Almost all taxa observed in the natural and restored meandering reaches were concentrated in the shallowest marginal habitats near the banks. Shear velocity increasing with water depth had a negative association with macroinvertebrate density and richness. 4. This study demonstrated that the shallow river bed along the inside of bends formed point bars that provided a highly stable substrate, a suitable habitat for macroinvertebrates in a lowland river. It is concluded that meander restoration could be an effective strategy for in-stream habitat restoration in lowland meandering rivers. Copyright (c) 2007 John Wiley & Sons, Ltd.
  • Daisuke Nakano, Shigeya Nagayama, Yoichi Kawaguchi, Futoshi Nakamura
    LANDSCAPE AND ECOLOGICAL ENGINEERING 4 (1) 63 - 68 1860-1871 2008/05 [Refereed][Not invited]
     
    Because of human impacts, lowland rivers are among the most degraded running water ecosystems, with their floodplains being the center of human activity. Recently, many programs to restore running water ecosystems have been undertaken using various methods in streams and rivers of North America, Europe, and Far East Asia. However, research and knowledge on the effects of river restoration in lowland rivers are limited around the world. The restoration project involving the first reconstruction of a meandering channel in Asia has been conducted in a lowland river section of the Shibetsu River, northern Japan. We review the geomorphologic and hydraulic characteristics of lowland rivers and their environments for macroinvertebrates and discuss approaches to restoring macroinvertebrate communities in lowland rivers, using insights from the restoration project in the Shibetsu River. It is concluded that the recovery of macroinvertebrate assemblages in channelized lowland rivers requires the implementation of restoration methods to create stable substrates.
  • Shigeya Nagayama, Yoichi Kawaguchi, Daisuke Nakano, Futoshi Nakamura
    LANDSCAPE AND ECOLOGICAL ENGINEERING 4 (1) 69 - 74 1860-1871 2008/05 [Refereed][Not invited]
     
    The Shibetsu River Restoration Project intends to reestablish a historic meander pattern by connecting a 3.5-km channelized reach with a series of oxbow lakes that were previously isolated by channel straightening. Prior to full-scale construction, a remeandering experiment (pilot) was conducted upstream of the project segment to assess the methods for and ecological responses to channel remeandering. Large wood (LW) structures were also installed in the experimental remeandering reach. The channel remeandering project with LW placement in a large lowland river is the first undertaken in Asia, and it has rarely been undertaken elsewhere. In this report, we present an overview of the Shibetsu River Restoration Project and the methods for and fish responses to channel remeandering and LW placement in the experiment.
  • Jung Il Seo, Futoshi Nakamura, Daisuke Nakano, Hidetaka Ichiyanagi, Kun Woo Chun
    WATER RESOURCES RESEARCH 44 (4) W04428  0043-1397 2008/04 [Refereed][Not invited]
     
    The fluvial export of large woody debris (LWD) was monitored in 131 reservoirs throughout Japan. Published data on the fluvial export of dissolved and particulate organic carbon were used to estimate the contributions of LWD in carbon budgets. Of all variables tested, watershed area was most important in explaining LWD carbon (LWDC) export, followed by annual precipitation. LWDC export per unit area was relatively high in small watersheds, highest in intermediate-sized watersheds, and decreased in large watersheds. In small watersheds, a large proportion of LWD retained on narrow valley floors may fragment or decay and eventually be exported in forms other than LWD. In intermediate-sized watersheds, LWD supplied from upstream and recruited by bank erosion is consistently transported downstream. In large watersheds, LWD recruitment is limited and LWD transported from upstream is stored on large floodplains. These differences in LWD recruitment, retention and transport in watersheds of different sizes lead to the proportion of LWDC in organic carbon exports to be maximum in intermediate-sized watersheds and decline rapidly in large watersheds.
  • 北海道の川の変貌と再生
    中村太士
    河川レビュー (143) 4 - 11 2008 [Not refereed][Not invited]
  • 本来の渓流環境が持つ生態系を支えるしくみ
    中村太士
    自然保護 (502) 7 - 9 2008 [Refereed][Not invited]
  • 永山滋也, 河口洋一, 中野大助, 中村太士
    Water science 水利科学研究所 51 (299) 60 - 77 0039-4858 2008 [Refereed][Not invited]
     
    河川内の倒木は、治水上の問題や舟運の阻害要因となることから、世界中の河川で管理上の障害物とみなされ、排除の対象となってきた。しかし、1970年代以降、北米太平洋岸地域を中心とした多くの研究により、倒木が河川生態系に果たす重要な役割が強く認識されるようになった。そして現在では、アメリカ、ヨーロッパ諸国、オーストラリア等において、河川内への倒木の投入が水生生物の生息場を改善する手法として有効であると広く認められ、実践されている。本論では、河川生態系に及ぼす倒木の役割を概観した後、これまで多くの研究が行われてきたサケ科魚類と倒木の関係に焦点をあて、倒木の役割および倒木を使った生息環境改善について、海外と日本における研究事例をそれぞれ紹介する。ここで、海外の研究事例については既存の代表的な知見をまとめたのに対し、日本の研究事例については、海外で得られた知見と比較し、日本において重要となるであろう論点を整理した。また、北海道標津川下流部において国内で初めて実施された大規模な倒木投入実験におけるサクラマスの応答についても紹介する。
  • Takumi Akasaka, Hisashi Yanagawa, Futoshi Nakamura
    Japanese journal of conservation ecology 日本生態学会 12 (2) 87 - 93 1342-4327 2007/11 [Refereed][Not invited]
     
    We investigated the use of various types of bridge as day roosts by several species of bats in Obihiro, Hokkaido. Eleven species belonging to six genera were found in the study area. Six species belonging to two genera used bridges as day roosts. The bridges were categorized into three types according to their structural characteristics. Bridges with flat undersurfaces were classed as flat-bottomed bridges; those with intersecting beams that formed deep cavities or cells on the undersurface were classed as cell bridges; and those with narrow parallel cavities on the undersurface were classed as stria bridges. Only cell and stria bridges were used as day roosts. Cell bridges were used more frequently than stria bridges. Bats created colonies in cell bridges, whereas almost all of the stria bridges were used as solitary roosts, particularly by juveniles. More species used stria bridges than used cell bridges. These results suggest that the type of bridge used by bats as day roosts depends on the bats' breeding stage. An increase in the use combined floorboard bridges, a new type of structure, may reduce the number of bridges potentially used by bats as day roosts.
  • Shigeya Nagayama, Futoshi Nakamura
    RIVER RESEARCH AND APPLICATIONS 23 (6) 671 - 682 1535-1459 2007/07 [Refereed][Not invited]
     
    We examined the relationship between the physical environment and habitat use of juvenile masu salmon, Oncorhynchus masou, in the Nobori River in Hokkaido, Japan to provide a perspective for the conservation of fish habitat in regulated streams. The study was undertaken during the autumn and winter, with an emphasis on the hierarchy of three spatial scales: microhabitat, channel-unit and reach scales. The microhabitat-scale analysis indicated juvenile masu salmon preferred a midstream habitat type, with a greater depth (Avg. +/- SD): 35.4 +/- 14.2 cm) and high (43.4 +/- 23.1 cm s(-1)) and uniform current velocities during the autumn, and a channel margin habitat type with a moderate current (about 20 cm s(-1)) and submerged cover during winter. In addition, different cover types have different roles in determining juvenile salmon distributions during winter. Grass cover had extremely high carrying capacities, whereas coarse substrate cover provided winter habitat for larger juvenile salmon. Channel-unit scale analyses showed that abundance of juvenile salmon tended to be higher in pools than runs in the autumn through winter. Reach-scale analysis showed that abundance and mean body length of juvenile salmon significantly differed between differently regulated reaches during winter, associated with the dominant cover type in each reach. This stud y demonstrated that the habitat conditions determining juvenile masu salmon distribution differ according to the season and scale of analysis. Therefore, for conservation of fish communities, it is important to evaluate and conserve or create fish habitats in regulated reaches, with a focus on the hierarchy of spatial scales and seasonal differences. Copyright (C) 2007 John Wiley & Sons, Ltd.
  • 中村 太士
    河川 日本河川協会 63 (6) 38 - 42 0287-9859 2007/06 [Not refereed][Not invited]
  • Futoshi Nakamura
    Japanese Journal of Limnology 68 (1) 61 - 63 0021-5104 2007/05 [Refereed]
  • Daisuke Nakano, Takumi Akasaka, Ayato Kohzu, Futoshi Nakamura
    BIRD STUDY 54 (1) 142 - 144 0006-3657 2007/03 [Refereed][Not invited]
     
    Capsule: Stable-isotope analysis indicated that terrestrial dipteran insects were the main food at a site in northern Japan. © 2007 British Trust for Ornithology.
  • Daisuke Nakano, Naotoshi Kuhara, Futoshi Nakamura
    JOURNAL OF THE NORTH AMERICAN BENTHOLOGICAL SOCIETY 26 (1) 103 - 110 0887-3593 2007/03 [Refereed][Not invited]
     
    We conducted a field experiment to evaluate the effects of habitat modification by aggregations of the case-building caddisfly Goera japonica Banks (Trichoptera:Goeridae) on the size structure and composition of benthic macroinvertebrate assemblages in a Japanese stream. We compared macroinvertebrate assemblages between cobbles with (intact treatment) and without (removal treatment) case aggregations of G. japonica. The total biomass of macroinvertebrates and Margalef's index did not differ between the treatments, but total abundance and taxon richness were higher in the intact treatment than in the removal treatment. Mean body length of macroinvertebrates was significantly smaller in the intact than in the removal treatment. Abundance of individuals in small (< 1.55 mm body length) and medium (1.55-3.00 mm) size classes was higher in the intact treatment than in the removal treatment, but abundance of individuals in the large (> 3.00 mm) size class did not differ between treatments. For 5 of the 9 dominant macroinvertebrate species, case aggregations facilitated colonization of individuals in small and medium size classes, but not of individuals in the large size class. Assemblage composition changed with habitat modification by the case aggregations. The interstitial spaces created by case aggregations of G. japonica would be at a spatial scale suitable for smaller individuals. Our results suggest that case aggregations of G. Japonica cases facilitate colonization by smaller individuals of certain species. This size-dependent and species-dependent facilitation indicates that the aggregation of case-building caddisflies can change the size structure and composition of benthic macroinvertebrate assemblages.
  • Futoshi Nakamura, Nozomi Shin, Satomi Inahara
    FOREST ECOLOGY AND MANAGEMENT 241 (1-3) 28 - 38 0378-1127 2007/03 [Refereed][Not invited]
     
    We examined the relationships between floodplain forest structure and disturbance frequencies in bar-braided and incised-meandering channel sections of the Rekifune River, northern Japan. This was undertaken with special reference to the life history traits at seedling and reproductively mature stages of eight dominant species (Chosenia arbutifolia, Populus maximowiezii, Toisusu urbaniana, Salix sachalinensis, Salix pet-susu, Alnus hirsura, Ulmus japonica, and Fraxinus mandshurica var. japonica). These species were generally arranged along the flood frequency and intensity gradient represented by five geomorphic surface types: gravel bar, lower and upper floodplain, secondary channel, and terrace. However, habitat separation between seedlings and conspecific mature stands occurred with geomorphic surface type in four of the eight species, suggesting that these species require more than one geomorphic surface type to complete their life cycles. Comparisons of stand-replacement disturbances between the bar-braided and incised-meandering rivers suggested that the shifting mosaic pattern in association with the evolution of land surfaces plays a vital role in maintaining variety in regeneration habitats and development of riparian forests in a half-century time scale. We conclude that the key factors maintaining the diversity of floodplain tree species in the studied northern temperate forests are: (1) the development of diverse geomorphic surfaces providing regeneration and habitat niches, and (2) the timing of maturation and lifespan of early and mid-successional species consistent with the disturbance frequency. (c) 2007 Elsevier BX All rights reserved.
  • 国土環境保全における治山の役割−過去、現在、そして未来−
    中村太士
    北海道民有林治山事業60周年記念講演会 (社)北海道治山林道協会 25  2007 [Not refereed][Not invited]
  • 中村太士
    森林技術 日本森林技術協会 (779) 2 - 5 1349-452X 2007 [Not refereed][Not invited]
  • 釧路湿原達古武沼の自然再生に向けて.
    中村太士
    陸水学雑誌 (68) 61 - 63 2007 [Refereed][Not invited]
  • T. Tsujimoto, K. Tanida, F. Nakamura, Y. Takemon, Y. Shimatani
    Ecology and Civil Engineering 応用生態工学会 10 (1) 63 - 71 1882-5974 2007 [Refereed][Not invited]
  • Futoshi Nakamura
    Ecology and Civil Engineering 応用生態工学会 10 (1) 47 - 58 1882-5974 2007 [Refereed][Not invited]
     
    The majority of published papers in ECE were relating to aquatic ecosystems and written by university and/or institute members. Other fields such as terrestrial or coastal ecosystems should be more focused, and consultant and government employee should be encouraged to submit their case studies. As a philosophy and a target of ECE, interdependence between ecology and civil engineering, holistic view of environment, target for restoration, and ecological health were discussed. At investigation and planning stage, life history trait, habitat condition, disturbance, material cycle, interactions between organisms were examined. The focus should be given to the key habitat corresponding to the key life-stage such as reproduction stage. IBI, RHS and habitat evaluation by GIS were introduced and other multivariate statistical analyses were employed. I believe that evaluation of ecosystem health in a broad scale is an important theme to build effective conservation or restoration plan. At the implementation stage, I doubt the necessity to draw the detail design of engineering structures, rather I feel it produce great mischief. Design with nature or passive restoration should be the first priority. The studies on this stage were very few, probably because evaluation of engineering works was not planned before implementation, and evaluation has not been fulfilled. Thus, at monitoring and evaluation stage, Before-After-(Reference) -Control-Impact design were recommended, and critical lines to refine or improve management plan and engineering works should be presented before implementation. © 2007, Ecology and Civil Engineering Society. All rights reserved.
  • 北海道標津川の本流と河跡湖におけるトビケラ相
    中野 大助, 久原 直利, 赤坂 卓美, 中村 太士
    陸水生物学報(Biology of Inland Waters) 22 37 - 45 2007 [Refereed][Not invited]
  • F. Nakamura, Y. S. Ahn
    Landscape Ecological Applications in Man-Influenced Areas: Linking Man and Nature Systems 209 - 233 2007 [Refereed]
     
    Kushiro Mire, a marsh located near the mouth of the Kushiro River, is suffering from the cumulative effects of pollution caused by land-use development in the watershed. A high wash load is of particular concern and accounts for approximately 95% of the total suspended sediment load that flows into the marsh. Researches have found that turbid water floods the margins of the marsh; this is due to riverbed aggregation in a channelized stream reach that provides agricultural drainage. An analysis of Cs-137 concentrations determined that the rate of fine sediment deposition was approximately three to eighttimes higher in the channelized reach than in a reach of the natural river. This rapid sediment deposition has lowered groundwater levels and enriched the nutrient content of the marsh soil. Consequently, woody species are rapidly invading the margins of the marsh, causing concern about a vegetation shift from reeddominated marsh to woodland. To address the physical and biological changes that are taking place in Kushiro Mire, various restoration projects have been planned and are being implemented under the Kushiro Mire Conservation Plan. Three examples of projects in the Kushiro Mire Conservation Plan are a restoration of the straightened river channel to meandering course, a forest restoration near Takkobu Lake, and a wetland restoration of a crane habitat. To develop pasture fields the natural meandering rivers in the Kushiro Mire have been channelized from the marginal areas of the marsh. The channelization projects lost pristine river-floodplain landscapes and inhibiting wildlife species. In the Kayanuma area, a river section extending about 2 km of Kushiro River is planned to restore from a straightened channel to a original meandering stream and floodplains. Monitoring and scientific evaluation will be conducted before and after the project and compared with downstream reference reaches. Fine sediments and nutrients have been accumulating in Takkobu Lake because of agricultural development and soil erosion in the uplands. The number of aquatic species in the lake has also been decreasing. An environmental assessment was undertaken in collaboration with "Trust Sarun", a non-profit organization, and sites were selected for conservation and restoration work. A larch forest was purchased to prevent it from being clear-cut and thus increasing sediment loading in the lake. The forest will be restored to its natural state. In addition, the Ministry of Environment in the Hirosato District acquired a wetland restoration site that was originally designated as an "ordinary area," i.e., the least regulated area of a national park. The restoration site is an abandoned agricultural field with an old drainage system developed in the 1960s; it is an important breeding habitat for red-crowed cranes (Grus japonesis). Based on a preliminary investigation, and under careful supervision to avoid disturbing the cranes, soil excavation and seeding experiments were undertaken and biogeochemical processes have been monitored. © 2007 Springer Netherlands.
  • Futoshi Nakamura, Satomi Inahara
    Plant Disturbance Ecology 283 - 310 2007 [Refereed][Not invited]
     
    The mechanism for maintaining species coexistence and richness in a forest is one of the central issues in plant community ecology. According to the first concept of niche partitioning, tree species are arranged along complex gradients of elevation, light, and edaphic conditions and form stand patches and canopy layers, thus partitioning a given habitat among the species present in the forest. The second concept of regeneration niche focuses on niche partitioning in reproduction, seed dispersal, seedling establishment, and further development of the immature plant. This chapter advocates the view that life history traits and their variations generate niche partitioning and tradeoffs, promoting tree coexistence in a community with heterogeneous abiotic and biotic conditions. Focusing on life history strategies and the likelihood of regeneration habitat occurrence, this chapter describes the relationships between a number of species and disturbance regimes. While it includes various disturbance regimes at a catchment scale, this review heavily relies upon the examples of Japanese rivers. However, much of the riparian studies in other regions, particularly in North America, lack variation in tree species and are limited to low-gradient alluvial rivers. Thus, roles of mass movement-type disturbances have been poorly studied. Further efforts in these gaps are required to develop a generality of species-disturbance relationships in riparian zones. © 2007 Elsevier Inc. All rights reserved.
  • WATANABE Keizo, NAKAMURA Futoshi, KOBAYASHI Miki, YANAI Seiji, YONEDA Takao, WATANABE Yasuharu, MARUOKA Noboru, KITAYA Hiroyuki
    Ecology and Civil Engineering 応用生態工学会 9 (2) 151 - 165 1344-3755 2006/12/20 [Refereed][Not invited]
     
    The purpose of this research is to explain the relationship between the winter habitat for juvenile masu salmon and three hierarchical structures: channel unit, subunit and microhabitat. The research was conducted at the Makomanai River and Shakotan River, southwest part of Hokkaido, from the middle to the end of December 2001. The natural stream reaches of both rivers are assigned as segment one. The three hierarchical stream structures are designated at the lower hierarchy under stream reaches. The channel unit is at the uppermost part, follows by subunit and then microhabitat. The results show that winter season environment of the juvenile masu salmon depends on two hierarchical stream structures, subunit and microhabitat. The winter season environment is related to combination of subunits close to the riverbank of the pool and glide that have relatively slow current velocity and small Froude number (Fr < 0.125), and the microhabitats with cover that have even slower current velocity. Not only is the microhabitat significant to winter season environment for juvenile masu salmon, but also the subunits around the microhabitat that have slow current velocity and small Froude number. We considered the subunits and microhabitats are very important habitat for the juvenile masu salmon before winter season in addition to the period during winter season. It is, therefore, suitable to regard the hierarchical characteristic of stream structure as contiguous habitat that shows seasonal change. Furthermore, we proposed river management methods with consideration of the winter season environment based on this research results as follows. We should be aware of conserving and creating channel unit with subunit and microhabitat for winter season by river management in the scale of the stream reach. In terms of microhabitat, we should pay attention to microtopography, vegetation and coarse woody debris.
  • Shigeru Mizugaki, Futoshi Nakamura, Tohru Araya
    CATENA 68 (1) 25 - 40 0341-8162 2006/12 [Refereed][Not invited]
     
    The purpose of this study is to describe the history of sediment deposition that has been occurring for several decades along the margins of the Kushiro Mire, into which the Kuchoro River drains. The dendrogeomorphic technique was used to examine an even-aged forest and adventitious roots to assess short-term (20 years) deposition rates and the frequency of heavy rainfall events. For medium- (40 years) and long-term (100 years) deposition rates, radiochronotogical analyses using Cs-137 and Pb-210 were also conducted. Several instances of high deposition rates caused by flooding events during the last 20 years were identified from the analysis of adventitious roots. The average sedimentation rate from 1963 to the present, estimated from the Cs-137 study, is over 1.3 cm/year. Using the Pb-210 dating method, based on a CFCS model which considered the organic matter content appropriate to wetland sediment, three deposition rates in the last 60 years were estimated: 2.0 cm/year from 1981 to 2000, 8.9 cm/year from 1975 to 1981, and 0.14 cm/year from 1939 to 1975. The analysis of environmental radionuclides indicated that the greatest sedimentation rates occurred in the years 1975 to 1981, when the Kuchoro River was extensively channelized and flood and/or precipitation events occurred. This suggests that land-use development and channelization introduced a large amount of sediment into the marginal areas of wetland through the drainage system and this was deposited on top of the peat soil. (c) 2006 Elsevier B.V All rights reserved.
  • Young Sang Ahn, Shigeru Mizugaki, Futoshi Nakamura, Yugo Nakamura
    GEOMORPHOLOGY 78 (3-4) 321 - 334 0169-555X 2006/08 [Refereed][Not invited]
     
    Environmental degradation, including shallowing, deterioration of aquatic habitat and water pollution, has arisen from the inflow of fine sediment to Lake Takkobu in northern Japan. The lake has experienced gradual environmental degradation due to agricultural development, which has introduced both fine sediment and sediment-associated nutrients into the lake. We have reconstructed the history of sediment yield to Lake Takkobu in Kushiro Mire over the last 300 years and have examined trends with reference to land-use development. Fifteen lake sediment core samples were obtained, and various physical variables of lake sediments were analyzed and dated using Cs-137 and tephrochronology. The physical variables showed that all points contained mainly silt, except for two points close to the river mouths, where the mean diameter was < 35 mu m. The peaks were defined as a "signal" when the physical variables were synchronous in a profile. These were created by floods and engineering works constructing drainage systems. The signal of canal construction in 1898 was detected in all core points. Lake Takkobu core samples contained two tephra layers. From the refractive indices of dehydrated glasses, the lower tephra layer was identified as Ko-c2 (1694) and the upper tephra layer as Ta-a (173 9). A clear peak in the Cs-137 concentration was detected at all the sampling points, except for the site close to the Takkobu River. This site showed two peaks in the Cs-137 concentration, which was attributed to perturbation from flood events and a drainage project. The maximum Cs-137 concentration was identified as the sediment surface from 1963, enveloped by the 1962 and 1964 signals. The sediment yield averaged over the last 300 years for Lake Takkobu was reconstructed for four periods using the signal, tephra and Cs-137 as marker layers. The sediment yield under the natural erosion condition for the first two periods was 226tons/year from 1694 to 1739 and 196tons/year from 1739 to 1898. The development of the Takkobu watershed started in 1880s with partial deforestation and channelization in 1898, 1959, and 1962 leading to an increased sedimentation yield of 1016tons/year from 1898 to 1963. Continued deforestation, channelization works in 1964, road construction in 1980-1990s, as well as agriculture development caused a further increase to 1354tons/year from 1963 to 2004. Compared to the averaged natural sedimentation yield of 206tons/year until 1898, initial land-use development in a catchment accelerated lake sedimentation, indicated by the 5-fold sediment yield. With increasing agricultural development since 1960s, sedimentation yields were highest for 1963-2004; a 7-fold increase compared with pre-impact conditions. To reduce sediment yield, riparian buffers along the rivers should be preserved or rebuilt, and sluices may function effectively during short-term periods of flooding. Environmental management policy and laws restricting uncontrolled and inappropriate land-use might help in addition to ensure longer-term environmental health by reducing the sedimentation rate. (c) 2006 Elsevier B.V. All rights reserved.
  • Daisuke Nakano, Futoshi Nakamura
    RIVER RESEARCH AND APPLICATIONS 22 (6) 681 - 689 1535-1459 2006/07 [Refereed][Not invited]
     
    The effects of restoration of channel meandering and of groyne structures on physical variables and river-dwelling macroinvertebrates were examined in a lowland river, the Shibetsu River in Northern Japan. The lowland segment of the Shibetsu River, which previously meandered, was straightened by channelization and groynes installed on some portions of the channelized reach. In 2002, the channelization works were partly reversed to improve the degraded river ecosystem. Physical environment variables and macroinvertebrate community structure and composition were compared among reconstructed meanders and channelized reaches with and without groynes. The shear stress of the river edge in reconstructed meanders and groyne reaches was lower than that in a channelized reach. In addition, the edge habitat near the stream bank created by the reconstructed meander and groyne reaches had higher total density and taxon richness of macroinvertebrates than those of the channelized reach. Restoration provided a relatively stable edge habitat, contributing to the recovery of macroinvertebrate communities in such channelized lowland rivers. The placement of groynes can be an effective method of in-stream habitat restoration for macroinvertebrates. Copyright (c) 2006 John Wiley & Sons, Ltd.
  • 中村太士
    フロント(水の文化情報誌) リバーフロント整備センター 18 (1) 16 - 18 1347-1848 2006 [Not refereed][Not invited]
  • 地形変化に伴う生物生息場形成と生活史戦略:人為的影響とシステムの再生をめざして.
    中村太士, 中野大助, 河口洋一, 稲原知美
    地形 27 (1) 41 - 64 2006 [Refereed][Not invited]
  • Daisuke Nakano, Futoshi Nakamura
    INTERNATIONAL ASSOCIATION OF THEORETICAL AND APPLIED LIMNOLOGY, VOL 29, PT 3, PROCEEDINGS 29 1377 - 1382 0368-0770 2006 [Refereed][Not invited]
  • 中野 大助, 久原 直利, 中村 太士
    日本陸水学会 講演要旨集 日本陸水学会 71 19 - 19 2006
  • Y Tachiki, T Yoshimura, H Hasegawa, T Mita, T Sakai, F Nakamura
    JOURNAL OF FOREST RESEARCH 10 (6) 419 - 427 1341-6979 2005/12 [Refereed][Not invited]
     
    The objectives of this study were to determine Global Positioning System (GPS) positional errors while moving under the forest canopy and to clarify the effects of polyline simplification on area and perimeter estimations. We used the Pathfinder Pro XR and GPSMAP 76S, which are categorized as '' high-end mapping '' and '' general navigation '' GPS receivers, respectively. The field tests were conducted in both natural and plantation forests. The results showed that the Pathfinder Pro XR, which has better multipath rejection technology, worked well, especially in the plantation forest under unfavorable conditions of higher stand density. We used analysis of variance to clarify the effects of the receiver type, positioning mode, stand type, and polyline simplification method on area and perimeter estimations. The receiver type and positioning mode were found to be significant factors that affected area estimation. The Pathfinder Pro XR estimated the area more accurately than the GPSMAP 76S, and differential GPS estimated the area more accurately than autonomous GPS. With respect to the perimeter, the receiver type, positioning mode, and polyline simplification method were found to be significant factors. The results showed that perimeter estimation was improved by using the velocity filter, and further improved by using the velocity filter and Douglas-Peucker algorithm, especially when the Pathfinder Pro XR was used. The GPSMAP 76S estimated the perimeter accurately without any filtering because its default speed filter worked well, even though the GPSMAP 76S is a general navigation GPS receiver.
  • H Yamada, F Nakamura, Y Watanabe, M Murakami, T Nogami
    HYDROLOGICAL PROCESSES 19 (13) 2507 - 2524 0885-6087 2005/08 [Refereed][Not invited]
     
    Permeability of a streambed is an important factor regulating nutrient and oxygen availability for aquatic biota. In order to investigate the relationship, an accurate permeability should be measured. However, it is difficult to measure permeability in a coarse gravel bed using a conventional permeability test. Moreover, turbulent flow may occur in coarse bed material, and then deviations from Darcy's law do occur. Thus, permeability calculated following Darcy's law may be overestimated under turbulent flow conditions and should be corrected. The packer test can be used in highly permeable gravel beds. We developed a field method applicable to a gravel bed using the packer test and derived an equation adopting a law of turbulent flow to study the problems under any type of flow condition. The accuracy of the equation was examined using a laboratory flume with a gravel bed. The results suggested that permeability calculated from Hvorslev's equation is overestimated for turbulent flow. In contrast, our equation, developed here, could evaluate permeability accurately under any type of flow condition. Copyright (c) 2005 John Wiley & Sons, Ltd.
  • F Nakamura, H Yamada
    ECOLOGICAL ENGINEERING 24 (5) 539 - 550 0925-8574 2005/05 [Refereed][Not invited]
     
    In the summer, the forest canopy lowers the water temperature, which is very important for anadromous fish, and its population density is significantly lower in grassland streams. Leaf litter and terrestrial invertebrates are the critical food resources for stream organisms. In a basin where the riparian forest is preserved, but other areas have been cut, the amount of leaf litter is almost equivalent to that in an intact natural basin. The annual input of terrestrial invertebrates falling into the forested reaches was 1.7 times greater than that in the grassland reaches, and fish biomass was significantly less in the grassland reaches. In-stream large woody debris creates storage sites for organic and inorganic matter and enhances habitat diversity for aquatic biota. However, the volume and number of large wood pieces decreased significantly with pasture development, because it clears the riparian forests and covers the riverbanks with grass. Fine sediment is a prominent by-product of agricultural development and adversely impacts periphyton productivity, the density and diversity of aquatic invertebrates, fish feeding, fish spawning and egg survival. We also examine the adequate width of a riparian buffer if it is to be able to satisfy its ecological functions. (c) 2005 Elsevier B.V. All rights reserved.
  • N Shin, F Nakamura
    PLANT ECOLOGY 178 (1) 15 - 28 1385-0237 2005/05 [Refereed][Not invited]
     
    Classification of riverbed geomorphic surfaces based on flooding frequency was conducted and the relationship between their distribution and river morphology was analyzed, to provide an understanding of the structure and species composition of riparian forests dominated by Chosenia arbutifolia. The channel floors of two contrasting river morphologies (bar-braided and incised meandering channels), were divided into five geomorphic surfaces (gravel bar, lower and upper floodplains, secondary channel, and terrace) based on the water level of a 2-yr and a 20-yr recurrence interval. The environmental variables of the same geomorphic surfaces showed similar trends regardless of braided and meandering channel morphology, but differed significantly among the five geomorphic surfaces, which influenced the dominance of tree species. The geomorphic surface map based on recurrence interval of flood and physiognomical vegetation map based on aerial photos appeared almost identical. Geomorphic surface distribution, determined by river channel dynamics and the sediment transport processes occurring at a larger scale and a longer time frame, played an important role in shaping the structure and composition of the riparian forests. C. arbutifolia dominated gravel bar, and the upper and lower floodplains, because these geomorphic surfaces were characterized by gravelly soils which have lower soil moisture availability than soils of other geomorphic surfaces. Thus, an extensive distribution of C. arbutifolia in the braided channel section can be attributed to the frequent lateral migrations of river channels, which resulted in a high ratio of gravel bars, and lower and upper floodplains. In order to preserve indigenous plant communities in riparian zone, dynamic nature and processes of braided rivers should be maintained.
  • KOHZU Ayato, KAWAGUCHI Yoichi, NUNOKAWA Masanori, NAKAMURA Futoshi
    Ecology and civil engineering 応用生態工学会 7 (2) 201 - 213 1344-3755 2005/01/30 [Refereed][Not invited]
     
    Stream restoration has been conducted in the Shibetsu River in northern Japan, which aims at the recovery of its river-floodplain ecosystem altered dramatically in the last 40 years. Well-designed monitoring before and after restoration should be conducted to evaluate the effects of the stream restoration on its ecosystem. An analysis of stable isotope ratios (δ-values) is one of the most effective methods for monitoring material cycling in river ecosystems. Because product δ-values are roughly dependent upon their source δ-values, we can trace material flows by comparing the δ-values of various compounds. In the first section of this review, we introduced a basic concept of the δ-value analysis by using an analogy from various diffusion patterns of salt water. The second section described how to calculate δ-values and discussed the difference between the analyses of natural stable isotope ratios and the tracer analyses (another powerful tool for material flow analysis). The third section presented the theoretical basis of mechanisms which change the δ-values. A product δ-value becomes different from its source δ-value in two kinds of processes: isotope exchange equilibrium and kinetic isotope fractionation. The magnitude of this difference (Δδ-value: δproduct-δsource) tells us about the processes and activities of the reactions. The fourth section introduced specific examples from the carbon and nitrogen δ-values (δ13C, δ15N) of aquatic organisms to infer the degree of eutrophication and carbon recycling at ecosystem levels as well as to determine food web structures and photosynthetic activities at biological interaction levels. In the fifth section, we presented the result of our study indicating differences in food web structure between a main-stream channel and oxbow lake in the Shibetsu River watershed when their δ13C and δ15N values of diverse aquatic organisms were compared. The advantages and limitations of the stable isotope analysis in environmental assessment were also discussed. © 2005, Ecology and Civil Engineering Society. All rights reserved.
  • 標津川における河川生態学術研究の取り組み
    中村太士
    RIVER FRONT (52) 22 - 25 2005 [Not refereed][Not invited]
  • 松田裕之, 矢原徹一, 波田善夫, 長谷川眞理子, 日鷹一雅, ホーテスシュテファン, 角野康郎, 鎌田麿人, 神田房行, 加藤真, 國井秀伸, 向井宏, 村上興正, 中越信和, 中村太士, 中根周歩, 西廣(安島, 美穂, 西廣淳, 佐藤利幸, 嶋田正和, 塩坂比奈子, 高村典子, 田村典子, 立川賢一, 椿宜高, 津田智, 鷲谷いづみ
    保全生態学研究 (10) 63 - 75 2005 [Refereed][Not invited]
  • NAKAMURA F.
    Landscape and Ecological Engineering 1 (1) 43 - 52 2005 [Refereed][Not invited]
  • KAWAGUCHI Yoichi, NAKAMURA Futoshi
    JAPANESE JOURNAL OF ECOLOGY 一般社団法人 日本生態学会 55 (55) 497 - 505 0021-5007 2005 [Refereed][Not invited]
     
    北海道東部を流れる標津川下流域では、国内で初めてとなる川の再蛇行化実験が実施された。実験は、直線化によって河道周辺に残された旧河道(河跡湖)の一つと、直線河道の再連結によって行われた。再蛇行化の前後に、直線河道と旧河道を村象として河道形状や地形に関する調査、藻類、底生動物、魚類に関する調査と安定同位体比による食物網構造の解析を行い、実験の評価を試みた。室内実験と再蛇行試験区での調査から、河道の分流部での流速分布や土砂の堆積を予測するモデルを組み立てた。再蛇行後の蛇行河道は、直線河道では見られない縦横断形状の変化が見られたが、水深、流速、底質といった物理環境要素は河道間で異ならなかった。再蛇行後、直線流路、蛇行流路ともクロロフィルa量は小さかったが、直線流路の堰き上げ下流部では著しく大きかった。蛇行流路(旧河道)の底生動物や魚類は、再蛇行化によって止水性から流水性に入れ替わった。底生動物にとって蛇行湾曲部の内岸側に形成される寄洲は重要な生息場であり、魚類にとっては外岸側で河岸浸食によって水中に倒れ込んだ樹木が重要な生息場であった。再蛇行前、直線流路と蛇行流路(旧河道)に生息する生物相の同位体比特性には違いがあり、両者の食物網構造は異なった。再蛇行化実験では個々の研究成果が得られ、現在は、個々の成果の補完や分野を横断する研究テーマの発掘を検討している。
  • Yôichi Kawaguchi, Futoshi Nakamura, Yuichi Kayaba
    Ecology and Civil Engineering 7 (2) 187 - 199 1882-5974 2005 [Refereed][Not invited]
     
    We investigated effects of experimental channel re-meandering on river ecosystem in lower reaches of the Shibetsu River, Hokkaido, northern Japan. Field samplings before and after re-meandering were conducted to compare fish species abundance and physical conditions of instream habitat to those in a straightened main channel (control reach). The reach used for re-meandering, an isolated old channel of the river, had been a stagnant lentic zone. Physical conditions in the past channel therefore were extremely different from those in control reach. Whereas a large number of lentic fish and crustaceans were found in past channel, only a few lotic fish were found in control reach. After re-meandering, physical conditions of past channel were dramatically changed and showed similar depth and velocity distributions to those in control reach. Re-meandering also greatly lowered lentic fish abundance. On the other hand, many masu salmon were also found in re-meandering reach. We recorded large-sized salmonids at a concave part of re-meandering reach, which were not found in control reach. The channel re-meandering improved its planar geometries and successfully restored diverse instream habitats complex in longitudinal and cross sectional structure. However, unlike past channel, limited availability of slow-flow habitats in re-meandering reach hindered lentic species to colonize. © 2005, Ecology and Civil Engineering Society. All rights reserved.
  • TACHIKI Yasuyuki, YOSHIMURA Tetsuhiko, HASEGAWA Hisashi, MITA Tomonori, SAKAI Tetsuro, NAKAMURA Futoshi
    Journal of The Japan Forest Engineering Society 森林利用学会 20 (1) 23 - 28 1342-3134 2005 [Refereed][Not invited]
  • NAKANO Daisuke, NUNOKAWA Masanori, NAKAMURA Futoshi
    Ecology and Civil Engineering 応用生態工学会 7 (2) 173 - 186 1344-3755 2005 [Refereed][Not invited]
     
    In March 2003, a re-meandering experiment, connecting main channel with an oxbow lake, was implemented in Shibetsu River, located in eastern Hokkaido, northern Japan. The objective of this study is to examine the changes in distribution and structure of macroinvertebrate community before and after the re-meandering experiment in the alluvial lowland river. We investigated composition of macroinvertebrate community in straight reach, oxbow lake (pre-experiment), and re-meandering reach (post-experiment). After the oxbow lake was connected with the main channel, we set five transect lines for quantitative evaluation of macroinvertebrate at three study reaches (natural meandering, re-meandering and straight channel). The hypothesis we tested was that the re-meandering reach containing more diverse habitat environments has more diverse macroinvertebrate community than do straight channel. The study results showed that most lentic species were replaced with lotic species after the connection. Most taxa identified on transects, however, were found at shallow shorelines of point bar, which we did not expect before the experiment. Since taxa richness and abundance were negatively correlated with shear velocity, a low shear stress and resultant bed stability at the shorelines of point bar are responsible for a high abundance and richness of macroinvertebrate community. Those results indicated a role of point bar for keeping abundance and diversity of macroinvertebrate in alluvial lowland river. Taxa richness and abundance of macroinvertebrate community in re-meandering channel had once recovered to the level of natural meandering channel in June, but this recovery was not maintained until November. We believe that this is due to the continuous movement and changes of bed material as well as channel morphology. The re-meandering reach is still dynamic and we have to monitor the physical process as well as ecological response until it reaches to the stable phase.
  • Yoichi Kawaguchi, Futoshi Nakamura
    Ecology and Civil Engineering 7 (2) 139 - 141 1882-5974 2005 [Refereed][Not invited]
  • H Shibata, O Sugawara, H Toyoshima, SM Wondzell, F Nakamura, T Kasahara, FJ Swanson, K Sasa
    BIOGEOCHEMISTRY 69 (1) 83 - 103 0168-2563 2004/05 [Refereed][Not invited]
     
    Water and dissolved nitrogen flows through the hyporheic zone of a 3rd-order mountain stream in Hokkaido, northern Japan were measured during a small storm in August 1997. A network of wells was established to measure water table elevations and to collect water samples to analyze dissolved nitrogen concentrations. Hydraulic conductivity and the depth to bedrock were surveyed. We parameterized the groundwater flow model, MODFLOW, to quantify subsurface flows of both stream water and soil water through the hyporheic zone. MODFLOW simulations suggest that soil water inflow from the adjacent hill slope increased by 1.7-fold during a small storm. Dissolved organic nitrogen ( DON) and ammonium NH4+ in soil water from the hill slope were the dominant nitrogen inputs to the riparian zone. DON was consumed via mineralization to NH4+ in the hyporheic zone. NH4+ was the dominant nitrogen species in the subsurface, and showed a net release during both base and storm flow. Nitrate appeared to be lost to denitrification or immobilized by microorganisms and/or vegetation in the riparian zone. Our results indicated that the riparian and hyporheic system was a net source of NH4+ to the stream.
  • 自然再生の目標像と空中写真利用
    中村太士
    林業技術 (742) 16 - 17 2004 [Not refereed][Not invited]
  • 蛇行河川を取り戻せるか
    中村太士
    フロント(水の文化情報誌) (2) 22 - 23 2004 [Not refereed][Not invited]
  • 川のあるべき姿を取り戻す.
    中村太士
    河川レビュー (125) 4 - 9 2004 [Not refereed][Not invited]
  • 森林と河川の相互作用−物理化学系ならびに生態系の視点から−.
    中村太士
    水工学シリーズ04-A-5.土木学会 A (5) 1 - 11 2004 [Refereed][Not invited]
  • 自然再生−地域(region),流域(catchment),地区(local site)における分析と復元の考え方.
    中村太士
    日本緑化工学会誌 30 (2) 391 - 393 2004 [Refereed][Not invited]
  • 中村太士
    林業技術 日本森林技術協会 (753) 2 - 6 1349-452X 2004 [Not refereed][Not invited]
  • F Nakamura, S Kameyama, S Mizugaki
    CATENA 55 (2) 213 - 229 0341-8162 2004/01 [Refereed][Not invited]
     
    The suspended sediment discharge in the Kuchoro River, a tributary of the Kushiro River, showed that wash load was about 90% of the yearly total suspended load carried into the wetland from the entire watershed. Seasonal floods associated with typhoons and snowmelt carried a large volume of wash load, 44% and 37%, respectively, of the yearly total wash load. The deposition of suspended sediment in the channelized section has aggraded the riverbed by 2 m in the past two decades, which has reduced the cross-sectional area of the channel, so that turbid water spills over and carries wash load and suspended sediment deep into the wetlands. Flooding of turbid water, in association with aggradation of the riverbed, was detected by using a Water Turbidity Index. The flooding and turbidity have significantly increased between 1984 and 1994. Similarly, a Normalized Difference Vegetation Index map showed that forest establishment has continued from the wetland margins and in areas adjacent to the river channel. The suspended sediment carried and deposited by floods and sediment-associated nutrients should alter the edaphic environment from wet nutrient-poor soil to dry nutrient-rich soil providing regeneration habitats for tree species. The vegetation in turn adds resistance and friction against flows and contributes to additional sedimentation. However, flooding and the associated high water table causes stress for trees and may lead to premature decay. Environmental variables, such as water level, water content, organic content and grain size, varied significantly along cross-sectional distance, and are likely regulated by deposition of fine sediments transported by floods. Electrical conductivity and total nitrogen in groundwater varied significantly along the longitudinal distance. Basal areas of willow and alder stands correlated with variables related to spread of turbid water, which indicates that eutrophication of groundwater indirectly affects marsh forest expansion. (C) 2003 Elsevier B.V. All rights reserved.
  • Takatoshi Nakamura, Hiroyuki Yamada, Yasunori Nakagawa, Yuki Kasai, Futoshi Nakamura, Tsunao Watanabe
    Ecology and Civil Engineering 7 (1) 53 - 64 1882-5974 2004 [Refereed][Not invited]
     
    Deteriorations of vegetation and hydrochemical environments were examined in the Hirosato restoration area on the margins of Kushiro Mire, where agricultural land use and a drastic increase of alder forest have influenced the ecosystem for the last past half-century. The vegetation was classified into seven types, where the meadow types dominate in the pasture area and the alder or fen types are distributed in the mire area. A following Canonical Correspondence Analysis shows two major results: 1) A vegetation gradient from the mire area to the pasture area corresponding to the obvious lowering of the groundwater level, 2) A vegetation gradient from the fen types to the alder types in correspondence to the lowering of the groundwater level and to the decrease of phosphorous concentration coupled with the increase of nitrogen concentration in soil water. The intense decrease of the groundwater level in the pasture area due to the diversion of the neighboring river has probably changed the mire vegetation into meadow vegetation, indicating that serious deteriorations have been introduced artificially. In the mire area, the distribution of the alder forest was mostly affected by hydrological regime in flooding, yet artificial influences could not be specified. © 2004, Ecology and Civil Engineering Society. All rights reserved.
  • Hiroyuki Yamada, Takatoshi Nakamura, Yasunori Nakagawa, Yuichirou Kamiya, Futoshi Nakamura, Tsunao Watanabe
    Ecology and Civil Engineering 7 (1) 37 - 51 1882-5974 2004 [Refereed][Not invited]
     
    The present study was conducted at Hirosato area in Kushiro Mire, where the aim of the nature restoration project by the Ministry of Environment is to restore pasture areas back to original mire. In order to understand the effects of pasture development and river improvement, the groundwater environment was investigated in pasture and surrounding areas. The results revealed that the mire area exhibited a transitional groundwater system from fen to bog. In comparison to the mire area, the average groundwater table in the pasture was lower with higher fluctuations. The pasture was developed along the Kyu-Setsuri River where the groundwater conditions are regulated by the river water level. This was greatly reduced by the diversion of the original course through artificial dikes. Thus the groundwater in the pasture was rapidly drained into the Kyu-Setsuri River. Moreover, Na+, Cl-, Mg2+ concentrations of groundwater were significantly lower in the pasture than in the mire area, suggesting a drainage of these nutrients from the pasture through the groundwater. In addition, the Ca2+ concentration of the groundwater in the pasture area was twice as high as in the mire area. This can be attributed to remains of calcium carbonate from pasture soil amendment, although about 30 years have passed since the pasture was developed. Furthermore, the river diversion by artificial dikes conducted almost 70 years ago has been influencing the groundwater system and its water quality. In order to restore the original groundwater environment, an increase of the water level of the Kyu-Setsuri River and the treatment of soil amendments are necessary. © 2004, Ecology and Civil Engineering Society. All rights reserved.
  • Y. Tachiki, T. Yoshimura, H. Hasegawa, T. Sakai, T. Owari, T. Mita, F. Nakamura
    Nihon Ringakkai Shi/Journal of the Japanese Forestry Society 86 (1) 5 - 11 0021-485X 2004 
    In this study, we measured the positioning accuracy of the Global Positioning System (GPS) while walking in forested areas and analyzed the GPS data to find factors that affected the positioning accuracy. In the field tests, we repeated GPS measurements with different types of GPS receivers, types of forests and modes of GPS positioning. The GPS data were analyzed using ANOVA. As a result, the type of GPS receivers, type of forests and modes of GPS positioning were found to be a significant factor (p < 0.001) to determine positioning accuracy while any interactions between these factors were not. The result also showed that the GPS receiver with multipath rejection technology produced higher positioning accuracy than without it. Therefore, multipath errors, which are caused by the reflection of GPS signals due to nearby stems, can be a critical cause to adversely affect GPS positioning accuracy. It was also suggested that GPS positioning accuracy while walking in forested areas was affected not by basal area but by stand density. That was because temporal signal blocking occurred more often with increasing stand density while walking forested areas. As a result of multiple regression analysis, the observed Position Dilution of Precision (PDOP) was not a significant factor (p = 0.590) to determine positioning accuracy.
  • NAKAMURA Futoshi
    Journal of Environmental Conservation Engineering 環境技術学会 32 (12) 968 - 975 0388-9459 2003/12/20
  • 佐川 志朗, 三沢 勝也, 妹尾 優二, 中村 太士
    魚類學雜誌 日本魚類学会 50 (1) 63 - 66 0021-5090 2003/05/23 [Refereed][Not invited]
  • Shirou Sagawa, Katsuya Misawa, Yuji Seo, Futoshi Nakamura
    Japanese Journal of Ichthyology 50 (1) 63 - 66 0021-5090 2003/05 [Refereed]
     
    We examined the selectivity of spawning habitat for shishamo smelt (Spirinchus lanceolatus) in December 2001 at pools and riffles of the Pon-warui stream, located in southern Hokkaido, Japan. We analyzed the sampling sites of fertilized shishamo smelt eggs in relation to environmental variables using principal component analysis and ANOVA. The results showed that the eggs were distributed to the pools with shallow (2-22 cm), slow moving water (-0.07-0.10 m/sec) and fine substrate (sand: particle size<2 mm). The eggs are normally dispersed downstream from the spawning ground (riffle or glide) by the stream current and should settle down against the bank of pools, highlighting the importance of preserving the pool-riffle sequence throughout the river system. © The Ichthyological Society of Japan 2003.
  • 河川氾濫原および湿原の再生
    中村太士
    緑の読本 (64) 54 - 60 2003 [Not refereed][Not invited]
  • 自然再生の考え方−その原則と適用−
    中村太士
    環境技術 (32) 44 - 51 2003 [Not refereed][Not invited]
  • 河畔緩衝帯の生態学的意義と草地開発が水辺の生態系に及ぼす影響.
    山田浩之, 中村太士
    Grassland Science 48 (6) 548 - 556 2003 [Refereed][Not invited]
  • Kazuya Takahashi, Seiko Hayashi, Futoshi Nakamura, Tamaki Tsuji, Susumu Tsuchiya, Hirofumi Imaizumi
    Ecology and Civil Engineering 5 (2) 139 - 167 1882-5974 2003 [Refereed][Not invited]
     
    This paper aims to propose the adequate buffer widths for preserving the ecological functions of riparian forests by reviewing both Japanese and international literatures and guidelines. The result of our review indicates the wide variations in the proposed buffer widths probably due to the differences in environmental backgrounds at each study site. The recommendation for the adequate buffer width for the conservation of each function is, thus, made considering Japanese landscape and vegetations. Approximately 30 m is required for maintaining shading effects and the provision of organic litter and woody debris which are especially important in the headwater to 3rd order mountainous streams. Water quality control is, on the other hand, more crucial in larger floodplain rivers with high potential of contaminations associated with urban development and agriculture. Regarding this function, 10~20 m buffer width is proposed as the minimum value in the literatures reviewed. The buffer width for aquatic habitat conservation should be determined by linking with other ecological functions, such as shading and organic litter input, thus about 30m is recommended in mountainous streams. Riparian forest functioning as habitat and corridor for terrestrial animals has different requirement for its width depending on the targeted species. Most of the recommended widths fall into the ranges up to 100 m and 200 m for the conservation of amphibians, reptiles and mammals and that of birds, respectively. Although this review focused mainly on the width of riparian forest, the future studies should put an emphasis on the longitudinal continuity along river or the whole stream networks for the establishment of more appropriate guidelines. © 2003, Ecology and Civil Engineering Society. All rights reserved.
  • Futoshi Nakamura
    Ecology and Civil Engineering 5 (2) 217 - 232 1882-5974 2003 [Refereed][Not invited]
     
    A river floodplain and wetland ecosystem is characterized by 1) interaction between terrestrial and aquatic ecosystems, 2) material flows such as sediment, organic matter, nutrients and heat energy moving from headwaters to the river mouth, and 3) flood pulse disturbances which inundate the floodplains. Unfortunately, rivers and floodplains (wetlands) in Japan no longer have these dynamic processes and interactions. Therefore, these fundamental characteristics should be revived through restoration projects. ‘Restoration’ using the strictest definition is a return to the original condition prior to human-induced damage. In many cases in Japan, however, self-sustaining ecosystems that provide important functions and habitats can often encouraged, which is called ‘rehabilitation’. Restoration projects proceed with clear objectives and targets. Before and after the implementation of a restoration project, well-designed monitoring should be followed and the results should be available to the general public. Ideally, the monitoring should be a Before-After-Reference-Control-Impact (BARCI) design, but there are many cases where no reference areas can be found near the restoration site or no replications were set because of large-scale project. The detail baseline data is required to implement field experiment, and those basic information as well as experimental results should be disclosed to general public through Internet. The most important principle in restoration projects is not the active intervention of humans, but “passive restoration”, which removes the limiting factors that continuously damage the present ecosystem. Take this first step and the resilient ecosystem will recover. In the Kushiro Mire, the largest in Japan, the prevention of sediment inflow, by establishing riparian forests and sedimentation ponds, is being planned and reclamation of abandoned pastures for wetlands is in progress. Projects to restore the original meandering channel and floodplains will be launched in the Kushiro and Shibetsu Rivers. These are pilot projects for the restoration of large ecosystems in Japan and adaptive management processes are being applied. Currently, an experiment to control the expansion of alder forests, by artificially raising the water table, is being conducted in the Kushiro Mire. Another experiment, where stream water was drained from the main channel of the Shibetsu River into an oxbow lake, is being evaluated for its ecological effects on river geomorphology, hydraulics, the food web, fish, vegetation, and water quality. © 2003, Ecology and Civil Engineering Society. All rights reserved.
  • 自然再生事業の方向性.
    中村太士
    土木学会誌 (88) 20 - 24 2003 [Refereed][Not invited]
  • 釧路湿原の現状と自然再生事業の概要.
    中村太士, 中村隆俊, 渡辺修, 山田浩之, 仲川泰則, 金子正美, 吉村暢彦, 渡辺綱男
    保全生態学研究 (8) 129 - 143 2003 [Refereed][Not invited]
  • TAKAHASHI Kazuya, TOKI Seiko, NAKAMURA Futoshi
    Journal of the Japanese Society of Revegetation Technology 日本緑化工学会 29 (3) 423 - 437 0916-7439 2003 [Refereed][Not invited]
     
    Many guidelines and ordinances to protect the ecological functions of riparian buffers have been introduced in the United States. This paper aims to review these American standards on riparian forest protection in order to examine the methods and principle of riparian buffer management guidelines and explore the feasibility to develop similar standards in Japan. The main objectives of riparian forest protection in the United States are 1) water quality control, 2) stream bank stabilization, 3) aquatic habitat protection and 4) terrestrial habitat and corridor conservation, for which the standard widths are established separately. In addition to buffer widths, riparian buffers within entire catchments and plant species composition have been discussed. Soft approaches such as incentives and education programs are also introduced to consolidate the effectiveness of standard settings. This review will provide important knowledge to establish Japanese guidelines for riparian forest management, which is urgently required to meet the increasing social demands on protecting the important ecological functions of riparian forests.
  • 立木靖之, 吉村哲彦, 長谷川尚史, 酒井徹朗, 尾張敏章, 三田友規, 中村太士
    日本林学会誌 86 5 - 11 2003 [Refereed][Not invited]
  • SAGAWA Shirou, YAMASHITA Shigeaki, SATOU Kimitoshi, NAKAMURA Futoshi
    JAPANESE JOURNAL OF ECOLOGY 一般社団法人 日本生態学会 53 (2) 95 - 105 0021-5007 2003 [Refereed][Not invited]
     
    Habitat use and diet variation of immature (age 0+ and age ≧1+) Sakhalin taimen (Hucho perryi) during fall were studied in second- and third-order tributaries of A Stream, northern Hokkaido, Japan. Sakhalin taimen aged 0+ were most abundant near the shore of the second- order tributary, whereas those aged ≧1+ were most abundant in the thalweg of the third-order tributary. The size of the fish was positively correlated with water depth and cover patch size. The composition of the stomach content differed markedly between masu salmon (Oncorhynchus masou) and Sakhalin taimen. The former comprised terrestrial insects (IRI% = 66.8), whereas the latter comprised ephemeroptera (IRI% = 62.9). These results indicate that the masu salmon is a typical drift forager, whereas the Sakhalin taimen shows benthos foraging. Fish, particularly the Siberian stone loach (Noemacheilus barbatulus tori) and the Amur stickleback (Pungitius sinensis sinensis), constituted a fairly large part (IRI% = 30.6) of the diet of Sakhalin taimen aged ≧1+. Furthermore, those aged ≧1+ cannibalized individuals of their own species aged 0+. In order to preserve immature Sakhalin taimen, migration routes throughout the river system must be maintained and bank cover with a slow water velocity, undisturbed stream beds for benthic invertebrates and riparian forest for terrestrial insects are required.
  • 高木麻衣, 中村太士
    日本林学会誌 85 214 - 221 2003 [Refereed][Not invited]
  • Tachiki Yasuyuki, Yoshimura Tetsuhiko, Sakai Tetsurou, Hasegawa Naofumi, Mita Tomonori, Kageyama Syoko, Nakamura Futoshi
    The Japanese Forestry Society Congress Database 日本森林学会 114 (0) 210 - 210 2003 
    林内における歩行状態でのGPS精度評価はこれまでに行われていない。今回の研究では北海道大学苫小牧研究林に設置されたGPSテストサイトを用いて、歩行状態のGPS測位精度を評価した。実験に使用した受信機はPathfinder Pro XR(Trimble)とGPSMAP76S(Garmin)である。実験では歩行者2名(歩行者A・B)、タイムキーパ1名を設定した。歩行者AはリアルタイムDGPSを行う受信機で測位を行いながら、秒速約0.66mで歩行した。歩行者Bは歩行者Aの後方、2秒後を歩行した。タイムキーパは時間情報を歩行者Aに与え、常に同じ速度で歩行できるようにした。苫小牧GPSテストサイトにはミズナラなどが生育する天然林とトドマツ人工林の中にテストサイトが設置されており、サイト一周に必要とする時間はそれぞれ4分16秒と3分15秒である。実験は2002年7月・8月(着葉期)と11月(落葉期)の2季節行われた。結果は季節、受信機の種類、補正方法、林相を要素として4元配置分散分析を行った。
    分析の結果、要素全てに有意な差が現れた。着葉期よりも落葉期のほうが精度が高くなると思われたが、実験中の衛星状態が夏のほうが良く、冬のほうが精度が悪くなった。着葉期と落葉期の受信衛星数を比較すると、着葉期のほうが平均1.5個衛星数が多かったことが原因であると考える。4元配置分散分析から、各要素の組み合わせを見ると、林相と受信機の組み合わせに優位な差が見られた。Pathfinder Pro XRでは天然林と人工林との測位精度がほとんど変わらなかった。一方、GPSMAP76Sは天然林においては良好な測位精度を得られたが、人工林では著しく悪化した。今回の実験から、測位中の衛星数の重要性と、受信機による測位精度の違いを把握できたと考える。
  • M. Takagi, F. Nakamura
    Nihon Ringakkai Shi/Journal of the Japanese Forestry Society 85 (3) 214 - 221 0021-485X 2003 [Refereed]
     
    The downstream effects of water regulation by dam were investigated in the Satsunai River where a flood control darn was initially impounded in 1996. The riverbed geomorphic surfaces were classified into four groups based upon the flooding recurrence interval. Five vegetation quadrats were set in each surface to measure basal areas of trees and environmental variables. The results indicated that species distribution was different among the geomorphic surfaces representing various environmental conditions. Seedlings of late-successional tree species dominated the geomorphic surfaces being frequently disturbed in the pre-regulation scheme where Salicaceae species such as Chosenia arubutifolia occupy the canopy layer presently. After the dam regulation, about 70% of the entire riverbed was classified as few flooding areas, suggesting that Salicaceae stands will be replaced by late-successional species, such as Fraxinus mandshurica var. japonica.
  • F Nakamura, FJ Swanson
    ECOLOGY AND MANAGEMENT OF WOOD IN WORLD RIVERS 37 (37) 279 - 297 0892-2284 2003 [Refereed][Not invited]
     
    Disturbance relevant to dynamics of wood in rivers can take many forms. We consider effects of ecosystem disturbance related to wood in river systems in geographic settings, which include high-gradient, boulder-dominated streams, braided, gravel-bed streams, and low-gradient, sand-bed streams. Disturbances of forests affect delivery of wood to streams and rivers directly by causing wood input or wood removal and indirectly by limiting source material. Disturbance of the fluvial system, either the channel form or flow regime, alters the transport and standing crop of wood. Change in wood distribution by processes of deposition, transport, and removal can disturb riparian, benthic (streambed), hyporheic, and water-column habitat. Human actions, such as harvesting trees, building roads, and regulating water flow, can substantially alter the types, frequencies, spatial patterns, and severity of the natural disturbance regime. We summarize the current status of knowledge on these points and identify knowledge gaps in studies of wood in rivers within the context of ecological disturbance. Finally, we offer a framework for future work and management that integrates processes that shape the spatial and temporal dynamics of wood at a series of scales.
  • Accuracy evaluation of low-cost GPS receivers at Tomakomai Test Range (TTR)
    Tachiki, Y, Yoshimura, T, Hasegawa, H, Mita, T, Sakai, T, Nakamura, F
    Proceedings of the international seminar on new roles of plantation forestry requiring appropriate tending and harvesting operations 138 - 143 2003 [Not refereed][Not invited]
  • H Yamada, F Nakamura
    RIVER RESEARCH AND APPLICATIONS 18 (5) 481 - 493 1535-1459 2002/09 [Refereed][Not invited]
     
    The Makomanai River in northern Japan has suffered considerable fine sediment deposition, especially in a reach where channel works have been constructed. Four contiguous reaches were examined for deposition of fine sediment and the effects of such on periphyton biomass; two of the reaches had channel works and bank protection, respectively, the other two being unmodified. The influence of fine sedimentation on epilithic periphyton biomass (chlorophyll a weight and organic matter weight) and the autotrophic index (AI), and the relationship between these and hydraulic variables was emphasized. Fine sediment increased, chlorophyll a decreased and AI increased in the reach with channel works and in the unmodified reach immediately upstream. In addition, the current velocity and Froude number tended to decrease in the reach with channel works. Correlation analysis showed that with an increase in fine sediment, chlorophyll a decreased and non-living periphyton, indicated by AI, increased. It was also confirmed that fine sediment increased with an increase in weight of periphyton organic matter and decreased with an increase in current velocity or Froude number. These results suggest that accumulation of fine sediment, which substantially reduces light penetration for photosynthesis under low current velocity conditions, results in lowered periphyton levels. The channel works have lowered the current velocity, thus promoting deposition of fine sediment and an increase in non-living periphyton. Copyright (C) 2002 John Wiley Sons, Ltd.
  • SAGAWA Shirou, NAKAMURA Futoshi, SEO Yuji, KIMURA Akihiko, MISAWA Katsuya, IRIE Kiyoshi, FUJITA Makoto, WATANABE Toshiya
    Ecology and civil engineering 応用生態工学研究会 5 (1) 85 - 102 1344-3755 2002/08/10 [Refereed][Not invited]
     
    The objective of this study was to establish working hypotheses in order to improve the structure and function of river regulation works. We examined the choices for spawning grounds of rainbow smelt (Osmerus mordax eperlanus) and the characteristics of spring habitat of other fish species (especially, amphidromous fish). The survey was made from May to June 2000, in the Warui and Pon-warui streams, located in southern Hokkaido, Japan. We analyzed the density and mortality of the rainbow smelt egg, and fish density in relation to environmental variables. The results of the analyses showed that rainbow smelt spawning grounds are distributed from the downstream to the upstream reach, and mainly located downstream from the altered reaches. Other fish species had own habitat choices respectively (e.g. Masu salmon Oncorhynchus masou selected pools with riparian forest cover), and a lot of amphidromous fish species also inhabit all reaches, however fish density declines with distance from the river mouth. Furthermore, rainbow smelt egg density and mortality were related to riparian forest cover. Without canopy cover (increased light levels) epilithic periphyton grows into a very thick covering, trapping fertilized rainbow smelt eggs as well as fine sediments on the streambed. Egg mortality was higher in the areas that had high epilithic periphyton biomass because of the thick deposition of fine sediment. Finally, two working hypotheses were presented for improvement of river regulation works. 1: Controlling the flow velocity over the altered section will facilitate upstream and downstream migration of fish populations, and will maintain the distribution of rainbow smelt spawning grounds and other fish species habitat downstream. 2: Replanting of riparian forests in the altered reaches will reduce egg mortality of rainbow smelt, and maintaining the meandering nature provided by geomorphic processes in the altered reaches will recreate habitats for masu salmon and other fish species. © 2002, Ecology and Civil Engineering Society. All rights reserved.
  • 実験的管理による湿原の保全・管理−釧路湿原.
    中村太士
    フロント(水の文化情報誌) (1) 60 - 63 2002 [Not refereed][Not invited]
  • 流域と川の変貌,そして再生への目標.科学
    中村太士
    岩波書店 72 (1) 74 - 76 2002 [Refereed][Not invited]
  • どうしたら自然再生事業は日本に根づくのか.
    中村太士
    JEAS News (96) 12 - 13 2002 [Not refereed][Not invited]
  • ダム堆砂量に関わる要因と生態系保全上の課題.
    中村太士, 竹門康弘
    応用生態工学 5 (1) 2002 [Refereed][Not invited]
  • 中村太士
    林業技術 日本林業技術協会 (721) 2 - 6 0388-8606 2002 [Not refereed][Not invited]
  • 森林の公益的機能の限界と可能性.
    中村太士
    土木学会誌 (87) 39 - 42 2002 [Refereed][Not invited]
  • 自然再生事業の現状と課題.
    中村太士
    環境研究 (126) 55 - 63 2002 [Not refereed][Not invited]
  • F Nakamura, M Jitsu, S Kameyama, S Mizugaki
    RIVER RESEARCH AND APPLICATIONS 18 (1) 65 - 79 1535-1459 2002/01 [Refereed][Not invited]
     
    The Kushiro Mire, the largest mire in Japan, presently faces the serious problem of turbid water flooding. Shortening of stream channels associated with agricultural development is a major cause of streambed aggradation. This aggradation reduces the carrying capacity of the channel, resulting in sediment laden water spilling over the wetlands in a flood event. Sedimentation progresses with repeated inundation by turbid water. which significantly alters the edaphic conditions, and thereby the composition and structure of marsh forests. Aggradation of the geomorphic surfaces with sedimentation lowers the water level, and increases soil particle size and nutrient status. This situation was clearly displayed in an ordination of canonical correspondence analysis. Among the environmental variables, water level was related most strongly to the pattern of a forest community. Salix species dominated the flood areas, which were characterized by a low water level, coarse sediment, and high electrical conductivity. Alnus japonica, the most common tree species in the Kushiro Mire, favors soil conditions represented by high water table and organic content. A. japonica adapts to a higher water level by developing lenticels with hypertrophied and adventitious roots. multiple sprouting and regenerates vegetatively. Basal areas (BAs) of A. japonica, however, seem to be limited by high fluctuations in water levels, which are amplified by channelization. This raises serious concerns for the integrity of the Kushiro Mire. It is important to implement a conservation plan from a watershed perspective because most problems originate in upper basins. Creating riparian buffer strips, sediment-filtering wetlands, and restoring the original meandering course may slow down sedimentation in the mire, and thus help to restore the natural hydrological regime. Copyright (C) 2002 John Wiley Sons, Ltd.
  • SAGAWA Shirou, YAMASHITA Shigeaki, NAKAMURA Futoshi
    JAPANESE JOURNAL OF ECOLOGY 一般社団法人 日本生態学会 52 (2) 167 - 176 0021-5007 2002 [Refereed][Not invited]
     
    The summer habitat of adult Sakhalin taimen (Hucho perryi) was studied in a fourth-order tributary of the Teshio River, Hokkaido. Sakhalin taimen selected large pools with slow water velocity and canopy shade or cover (especially canopy shade). The maximum number of Sakhalin taimen observed in pools during three censuses was positively correlated with the percentage of canopy shade or cover, while the maximum body size was positively correlated with the bed area. The study section had a reach within some nature-oriented river works, but no taimen were found there, probably because of insufficient pool sizes and canopy shade or cover patch for this species. On the other hand, Sakhalin taimen in this study stream are known to spawn from May to June in first-, second- and third-order streams where meandering channels and riparian forests are well preserved. These results suggest the importance of preserving large deep pools with canopy shade or cover and allowing adult taimen to migrate upstream (first-, second- and third-order streams) and downstream (fourth-order streams) throughout the river system.
  • Futoshi Nakamura, Yasuhiro Takemon
    Ecology and Civil Engineering 5 (1) 125 - 127 1344-3755 2002 [Refereed]
  • Experimental Study on Benthic Fish Habitats in an Ice Covered River
    T. Nogami, Y. Watanabe, M. Nakatsugawa, F. Nakamura, K. Kamura, H. Yamada, S. Tsuchiya, K. Watanabe, H. Iwase
    Ice in the Environment: Proc. of the 16th IAHR International Symposium on Ice, Dunedin, International Association of Hydraulic Engineering and Research 104 - 110 2002 [Refereed][Not invited]
  • Field Experiments for Mitigation Benthic Fish Habitats in the Makomanai River
    T. Nogami, Y. Watanabe, M. Nakatsugawa, F. Nakamura, K. Kamura, H. Yamada, S. Tsuchiya, K. Watanabe, H. Iwase
    River Flow 2002 541 - 549 2002 [Refereed][Not invited]
  • Effects of Dams and Channel Works on Riverine Habitat in Mountainous Streams
    F. Nakamura, H. Yamada, N. Shin
    Proc. of the 1st International Symposium on Conservation of Mountain Ecosystems 2002 [Not refereed][Not invited]
  • S Kameyama, Y Yamagata, F Nakamura, M Kaneko
    REMOTE SENSING OF ENVIRONMENT 77 (1) 1 - 9 0034-4257 2001/07 [Refereed][Not invited]
     
    A new water-turbidity index (WTI) based on multispectral images was developed and tested at Kushiro Mire, eastern Hokkaido, Japan. An algorithm for turbidity estimation was developed and applied to Landsat TM images to monitor the turbid water on the mire surface during the snow-melting season. We used spectral mixture analysis (SMA) to produce a turbidity estimation model. The SMA "unmixes" a mixed pixel determining the fractions due to each spectral end member. In this study, we used four end members (1, alder; 3, reed; 3, high-concentration turbid water (485 ppm); 4, low-concentration turbid water(10 ppm) measured in the test site. The WTI was determined by the following equation: WTI = a(max)/(a(max) + a(min)), where a(max) is abundance of high-concentration turbid water and a(min) is abundance of low concentration turbid water. The end-member spectra of alder and reed were measured in the laboratory using specimens collected at the test site. The spectrum of turbid water was measured at the test sites. The relative abundance of each end member was estimated based on this spectral information using SMA. The same formula was applied to Landsat TM images. Then we applied the WTI equation to the end-member images to obtain a WTI map. In the mire wetland region, turbid water spreads under alder trees and reed grasses. Tb verify our turbidity estimation method based on WTI under these conditions, we constructed a small experimental wetland consisting of mixed stands of alder acid reed. WTI was calculated from the mixed spectrum of this "artificial wetland" and the regression curve for the relation between WTI and the actual turbidity was determined (R-2=.91). Finally, this regression equation was used to derive a turbidity map from the WTI image. (C) 2001 Elsevier Science Inc. All rights reserved.
  • パートナーシップによる新しい川づくり.
    中村太士
    フロント(水の文化情報誌) (2) 64 - 67 2001 [Not refereed][Not invited]
  • 中村太士
    フロント(水の文化情報誌) リバーフロント整備センター 13 (5) 60 - 63 1347-1848 2001 [Not refereed][Not invited]
  • 中村太士
    フロント(水の文化情報誌) リバーフロント整備センター 13 (8) 60 - 63 1347-1848 2001 [Not refereed][Not invited]
  • 中村太士
    河川 日本河川協会 57 (3) 6 - 11 0287-9859 2001 [Not refereed][Not invited]
  • 中村太士
    フロント(水の文化情報誌) リバーフロント整備センター 14 (11) 60 - 63 1347-1848 2001 [Not refereed][Not invited]
  • 中村太士
    河川 日本河川協会 57 (11) 15 - 19 0287-9859 2001 [Not refereed][Not invited]
  • 中村太士
    水情報 〔月刊水情報〕 21 (11) 13 - 17 0917-1770 2001 [Not refereed][Not invited]
  • Keizo Watanabe, Futoshi Nakamura, Kunishige Kamura, Hiroyuki Yamada, Yasuharu Watanabe, Susumu Tsuchiya
    Ecology and Civil Engineering 4 (2) 133 - 146 1882-5974 2001 [Refereed][Not invited]
     
    The influence of stream alteration on abundance of benthic fish was examined hierarchically by both reach and channel unit scales, in the Makomanai River, in Sapporo City, northern Japan. Study sections of 2 km were settled in bank protection, natural, and channel works courses. The density of Cottus nozawae in the channel works reach was significantly lower than that in the natural and bank protection reaches, whereas the abundance of Noemacheilus barbatulus toni was not different among the three reaches. The density of C. Nozawae was positively correlated with the abundance of boulders and loose stones, probably because interstitial spaces on river bed provide refuge and critical habitat components for living and spawning. River bed in the channel works reach was covered by fine sediment and with few loose stones, resulting in reduced interstitial spaces and thus a low density of C. nozawae. Within the channel unit, the density of C. Nozawae in riffles was significantly higher than that in pools, which could be attributed to abundant boulders and loose stones in riffles. A reduced tractive force in the stream caused by check dams and bed stabilization works not only promotes the deposition of pebble-sized stones and the creation of a stable channel bed during a flood, but also traps fine sediment during low-flow periods. These physical mechanisms changes, in association with the channel works, greatly altered the habitat required for C. nozawae. © 2001, Ecology and Civil Engineering Society. All rights reserved.
  • Marie Murakami, Hiroyuki Yamada, Futoshi Nakamura
    Ecology and Civil Engineering 4 (2) 109 - 120 1882-5974 2001 [Refereed][Not invited]
     
    The fine sediment (< 2 mm) effects on percentage of openwork gravel and hydraulic conductivity were studied at 5 small catchments in southwestern Hokkaido, Japan in 1999. We also examined the influence of land use on substrate and hydraulic conductivity. Bed material was sampled using the frozen core technique and hydraulic conductivity was measured using the packer test. The percentage of openwork gravel and hydraulic conductivity decreased with an increase in proportion of fine sediment. Especially the weight percentage of 0.125 to 1.0 mm showed the most negative correlations with these parameters, which indicates that fine sediment filling the interstitial space of gravel bed is responsible to the decreases in these parameters. The stream containing great amount of fine sediment had extensive agricultural development in its catchment area. Thus these substrata differences among the streams were attributable to the surface soil erosion and bank erosion at agricultural fields. Fine sediment progressively accumulated in streambed materials under normal flow conditions, resulting in a decrease in openwork gravels and hydraulic conductivity. Losing the interstitial space of gravel bed will have detrimental effects on benthic fish and invertebrate and other aquatic biota that require these habitats in their life cycles. In order to maintain healthy stream ecosystem, we need to pay more attention on the conditions of fine sediment and bed materials, and to seek effective measures to prevent fine sediment production and deposition. The sampling methods applied in this study were proved to be useful to investigate fine sediment and hydraulic conductivity of the bed materials. © 2001, Ecology and Civil Engineering Society. All rights reserved.
  • NAKAMURA Futoshi
    Landscape Ecology and Management Japan Association for Landscape Ecology 6 (3) 107 - 107 1345-532X 2001
  • SHIN Nozomi, NAKAMURA Futoshi
    Landscape Ecology and Management Japan Association for Landscape Ecology 6 (3) 115 - 117 1345-532X 2001
  • IKEGAMI Yoshiyuki, NAKAMURA Futoshi
    Landscape Ecology and Management Japan Association for Landscape Ecology 6 (3) 127 - 132 1345-532X 2001
  • F Nakamura, N Shin
    GEOMORPHIC PROCESSES AND RIVERINE HABITAT 4 173 - 181 2001 [Refereed][Not invited]
     
    Dams for water regulation substantially alter the regeneration habitats of riparian species, thereby affecting their recruitment, composition and growth rate. This paper examines the effects of darns on the dynamics of riparian forests. First, the distribution of dominant riparian tree species was investigated in the Rekifune River, where no dams have been built and their regeneration habitats were classified into five geomorphic surfaces based upon flooding frequency. Chosenia arbutifolia and Toisusu urubaniana appear on the most flood prone areas such as gravel bars and lower floodplains. Poplus maximowiczii also prefers coarse sediment, but establishes on upper floodplains. The late successional species, such as Ulmus davidiana var. japonica and Froxinus mandshurica var. japonica, occur on stable surfaces referred to as terraces where sand and fine gravel make up the soil. Salix spp. dominates secondary channels. Second, the effects of dams on the regeneration process were examined in the Satsunai River where a flood control dam was completed in 1997. Spring floods in snowy regions mobilize riverbed sediment and create the moist, alluvial substrate ideal for seed germination. These habitats are essential for the recruitment of salicaceous species. Dams, in general, attenuate spring flooding and/or stabilize summer flows. This flow regime limits the development of gravel bars and reduces flood fequency. A decrease in flood frequency and magnitude may reduce the densities of pioneer species and shift species distribution from pioneer to late sucessional species.
  • F Nakamura, FJ Swanson, SM Wondzell
    HYDROLOGICAL PROCESSES 14 (16-17) 2849 - 2860 0885-6087 2000/11 [Refereed][Not invited]
     
    Geomorphological processes that commonly transport soil down hillslopes and sediment and woody debris through stream systems in steep, mountainous, forest landscapes can operate in sequence down gravitational flowpaths, forming a cascade of disturbance processes that alters stream and riparian ecosystems. The affected stream and riparian landscape can be viewed through time as a network containing a shifting mosaic of disturbance patches - linear zones of disturbance created by the cascading geomorphological processes. Ecological disturbances range in severity from effects of debris flows, which completely remove alluvium, riparian soil and vegetation along steep, narrow, low-order channels, to localized patches of trees toppled by floating logs along the margins of larger channels. Land-use practices can affect the cascade of geomorphological processes that function as disturbance agents by changing the frequency and spatial pattern of events and the quantity and size distribution of material moved. A characterization of the disturbance regime in a stream network has important implications for ecological analysis. The network structure of stream and riparian systems, for example, may lend resilience in response to major disturbances by providing widely distributed refuges. An understanding of disturbance regime is a foundation for designing management systems. Copyright (C) 2000 John Wiley & Sons, Ltd.
  • 中村太士
    フロント(水の文化情報誌) リバーフロント整備センター 12 (5) 64 - 67 1347-1848 2000 [Not refereed][Not invited]
  • 中村太士
    フロント(水の文化情報誌) リバーフロント整備センター 12 (8) 64 - 67 1347-1848 2000 [Not refereed][Not invited]
  • 中村太士
    フロント(水の文化情報誌) リバーフロント整備センター 13 (11) 64 - 67 1347-1848 2000 [Not refereed][Not invited]
  • NAKAMURA Futoshi
    Landscape Research Japan Online 社団法人日本造園学会 64 (2) 131 - 134 1340-8984 2000 [Refereed][Not invited]
  • Y. Adikari, S. I. Kikuchi, F. Nakamura
    Chikei 21 (2) 193 - 207 0389-1755 2000 [Refereed][Not invited]
     
    The erruption of Mount Tokachi volcano in central Hokkaido, Japan, in May, 1926, triggered the Taisho Mudflow which devastated about 600 ha of forest in Furano River basin on the northwestern slope of the volcano. The Taisho Mudflow scar was surveyed to clarify the different mudflow regimes, to discover differences in plant cover and to relate them to sediment properties. We classified the study area into three different zones according to the characteristics of the surface sediment materials and location: Scoured Zone (SZ), Upstream Deposited Zone (UDZ) and Downstream Deposited Zone (DDZ). Sediment pedons were described. The physical and chemical properties, and plant cover were studied at sixteen sites in the three different zones. Comparing sediment pedon characteristics we found out that the three zones were different in color and volcanically originated substrates, and the SZ had an exposed B or C horizon with a fragipan layer. On the other hand, UDZ and DDZ had horizons characteristic of alluvial deposits forming IIA and IIB mineral soil horizons just below the O horizon. Laboratory analysis showed that soil water content, bulk density, texture, Al/Ca ratio and organic matter content were significantly different (p<0.05) among the scoured and deposited zones irrespective of location. The organic matter content in the SZ was significantly lower, whereas the Al/Ca ratio was much higher than in the other two zones. The total basal area of the overstory was significantly lower (p<0.05) in the SZ as compared to the UDZ and DDZ. Moreover, tree density was significantly different (p<0.05) among the three zones. On the other hand, understory total basal area was significantly higher (p<0.05) in the SZ. Relating soil nutrient availability to the vegetation parameters we found that the Al/Ca ratio and soil texture controlled the stand structure and composition in the three zones of the Taisho Mudflow.
  • MORIMOTO Yukihiro, NAKAMURA Futoshi
    Landscape Ecology and Management Japan Association for Landscape Ecology 5 (3) 77 - 77 1345-532X 2000
  • 微細砂堆積による河床透水性の低下がサクラマス卵の生残率に及ぼす影響
    山田浩之, 中村太士
    日本林学会北海道支部論文集 49 112 - 114 2000 [Refereed][Not invited]
  • A Nagasaka, F Nakamura
    LANDSCAPE ECOLOGY 14 (6) 543 - 556 0921-2973 1999/12 [Refereed][Not invited]
     
    Temporal changes in a hydrological system and riparian ecosystem were examined with reference to land-use conversion in order to clarify the linkages between these two systems. First, the hydrological system of the Toikanbetsu River basin was divided into three components that measure water retention, inundation and conveyance. Variation in the hydrological system was expressed as a basis of delineating the three components and estimating their functions. The rainfall-runoff system was also examined using a model which can predict responses of surface-, subsurface- and base flows on rainfall intensity. Second, areas and fragmentation of the riparian forests, maximum stream temperature in summer and amount of coarse woody debris (CWD) were selected as parameters indicating the condition of the riparian ecosystem. Temporal changes in stream temperature and amount of CWD were estimated using multiple regression analysis and analysis of variance, respectively. The results indicated that the hydrological system has been altered since the 1970s, increasing flood peaks by 1.5-2.5 times and shortening peak appearance by 7 hours. Riparian forests have been disappearing since the 1960s due to extensive development of agricultural lands and river channelization. The summer maximum stream temperature increased from 22 degrees C in 1947 to 28 degrees C at present. The amount of CWD should substantially decrease with river channelization and associated forest cutting. Fish favoring cool water, such as masu salmon, could survive in 1947 although they are forced to migrate to cooler forested upstream tributaries now. The ecological systems were closely related to and distinctly altered by land-use. Finally, we propose a new perspective for understanding the two interrelated systems. Riparian ecosystems can be restored by restoring water retention and inundation functions, which also reduce the flood hazard generated by elevated flood peaks.
  • 水辺環境の保全と景観生態学.
    中村太士
    科学(岩波書店) 69 (12) 1029 - 1035 1999 [Refereed][Not invited]
  • Futoshi Nakamura
    Ecology and Civil Engineering 2 (2) 125 - 139 1882-5974 1999 [Refereed][Not invited]
     
    Riparian forests play an important role in a river ecosystem. Dams for water regulation and erosion control substantially alter the regeneration habitats of riparian species, thereby affect their recruitment, composition and growth rate. This paper reviewed the effects of dams on riparian forest dynamics. The effects of dams can be seen in the regulation of water discharge, sediment transport and frequency of flood disturbances. For example, spring floods in snowy regions mobilize riverbed sediment and create the moist, alluvial substrate ideal for seed germination. These are essential habitats for the recruitment of Populus and Salix spp. In contrast, dams attenuate spring flooding and/or stabilize summer flows. This flow regime limits the development of sand bars and may induce drought stress for seedlings and old trees. The recent degradation of riverbeds, widely observed in Japan, is due to gravel mining, and sediment entrapment by reservoirs and erosion control dams. This situation provides stable habitats for riparian forests, resulting in expansion of woodlands. However, decreased flood frequency and magnitude along the downstream reach of dams may reduce densities of pioneer species and shift species distribution from pioneer to late successional trees. Seed dispersal by water which is especially important for maintaining species diversity in wetland forests may be affected by dam construction. The methodologies applied to previous studies on dam effects are based upon a paired-reach comparison (up- and downstream) and/or comparison among rivers with and without dams. Some studies only examine differences in species composition, but others analyze species distribution and population densities with hydrologic, geomorphic parameters. Pre- and post-regulation effects were examined by dendrochronological analysis of core samples taken from matured trees and interpretation of a series of air-photos. Simulations were also conducted based upon niche differentiation and forest succession models. In order to mitigate the effects of dams, I suggest that an adaptive management strategy, such as initiation of artificial floods, is required. © 1999, Ecology and Civil Engineering Society. All rights reserved.
  • 放射性降下物を用いた釧路湿原河川流入部における土砂堆積厚の推定
    水垣滋, 中村太士
    日本地形学連合学会誌(地形) 20 (2) 97 - 112 1999 [Refereed][Not invited]
  • 岸千春, 中村太士, 井上幹生
    日本生態学会誌 49 11 - 20 1999 [Refereed][Not invited]
  • Toshio Abe, Futoshi Nakamura
    Ecology and Civil Engineering 2 (2) 179 - 190 1882-5974 1999 [Refereed][Not invited]
     
    Experimental removal of coarse woody debris (CWD) was conducted in a low-gradient, second-order stream covered by deciduous riparian forest in northern Hokkaido, Japan. We examined channel morphology, habitat variables and fish densities in 2 study reaches (cleaned and control, 100 m length) during autumn (Sept. - Oct.) of 1993, spring (May - Jun.) and autumn (Sept. - Oct.) of 1994. Immediately after the first survey, CWD and other small organic materials within the cleaned reach were removed by hand or hand-winch. Aggraded areas in the cross-sections of the cleaned reach were larger than those of the control reach during the autumn of 1993 - spring 1994. Cross-sectional changes tended to correlate with channel variables, such as curvature and width, in the cleaned reach, and with CWD amounts in the control reach. After CWD removal, small pools associated with CWD disappeared and pool number decreased, but pool volume did not vary. Cover area decreased, but depth, velocity, and substrate did not change in the cleaned reach. Density of juvenile masu salmon (Oncorhynchus masou) declined rapidly, but that of stone loach (Noemacheilus barbatulus toni), a benthic fish, did not show any significant changes. Deposition of sediment after CWD removal was associated with development of gravel bars at channel bends or wider sections. Pools were recreated by lateral scouring at the opposite sides of banks where gravel bars developed. We concluded that CWD pieces play an important role in forming pools and controlling pool number, although they are not effective in increasing pool volume in low-gradient meandering streams. Thus, a decline in masu salmon population could be attributed to a decrease in cover and pool number in this stream. © 1999, Ecology and Civil Engineering Society. All rights reserved.
  • 笹岡英二, 矢島崇, 渋谷正人, 高橋邦秀, 中村太士, 清水収
    日本林学会誌 81 22 - 28 1999 [Refereed][Not invited]
  • 中村 太士
    国際景観生態学会日本支部会報 Japan Association for Landscape Ecology 4 (4) 68 - 69 1345-532X 1999
  • Chiharu Kishi, Futoshi Nakamura, Mikio Inoue
    Japanese Journal of Ecology 49 (1) 11 - 20 0021-5007 1999 
    Inputs, outputs, and retention of leaf litter from deciduous riparian forest were examined in a headwater section of Horonai Stream, a low-gradient, gravel-bed stream in southwestern Hokkaido, Japan. During the leaf-fall season (late September-early November), total inputs exceeded total outputs, and 56% of the former was stored in the stream section. In contrast, during the post-leaf-fall season (mid November-early March), total outputs amounted to 609% of total inputs, suggesting that leaf litter stored during the leaf-fall season was decreased by fluvial transport after all of the leaves had fallen from the riparian trees. Correspondingly, leaf litter retention was highest in late autumn (November), followed by early spring (March), and the lowest in early summer (June). Irrespective of season, pools were more retentive than riffles. Further more, leaf litter retention in riffles and pools increased with woody debris abundance in autumn and early summer, respectively. Pools and woody debris were suggested to be important retention structures in the low-gradient, gravel-bed stream.
  • S. Mizugaki, F. Nakamura
    Chikei 20 (2) 97 - 112 0389-1755 1999 [Refereed]
     
    Since the 1960's, the watershed areas draining into the Kushiro Mire, the largest mire in Japan, have been developed intensively for agricultural lands and residential areas. In association with land-use development, most rivers were channelized. The Kuchoro River basin, one of the rivers flowing into the mire, also was developed and channelized. Agricultural land-use development produced a large amount of fine sediment and the river aggradation at the boundary of the mire caused inundation of the turbid floods over the wetlands. The sediment accumulation alters the original flora of vegetation on the mire and promotes the establishment of willow trees. The objective of this study is to clarify the accumulation rate of fine sediment from the Kuchoro River since the 1960's. We estimated the thickness of the accumulated sediment from 1963 to present using Cs-137 concentration analysis. The estimated thickness of sediment at 2m away from the river channel was 210 cm for 34 years, or 6.2 cm/year. This rate is three to eight times higher than previous studies carried out in wetlands, USA. Moreover we also estimated the sedimentation rate since the 1980's by the ages of adventitious roots. This dendrochronological analysis and additional air-photo interpretation clarified that trees had been established in 1981 after the large flooding with high precipitation.
  • Futoshi Nakamura
    Ecology and Civil Engineering 2 (2) 101 - 102 1344-3755 1999 [Refereed]
     
    The experimental flood from Glen Canyon Dam in spring 1996 and Columbia basin program to bring back salmon in the 1980s initiate a new era of dam management in the United States. Conservation and improvement of river environment was included in the purpose statement of the new River Law in Japan, which was revised in 1997. Reservoir dams, erosion control dams and other dam structures are thought to have considerable effects on the structure and function of river ecosystem, but very few studies in Japan have demonstratively elucidated such effects. In order to provide present knowledge on influences of dam structure, studies in Japan and other countries were reviewed from the viewpoints of hydraulics, geomorphology, riparian forest dynamics, water quality, benthic animals, and fish life history. We believe that the idea of Adaptive Management will be useful as a future management strategy within a limited knowledge of dam influences. © 1999, Ecology and Civil Engineering Society. All rights reserved.
  • E. Sasaoka, T. Yajima, M. Shibuya, K. Takahashi, F. Nakamura, O. Shimizu
    Nihon Ringakkai Shi/Journal of the Japanese Forestry Society 81 (1) 22 - 28 0021-485X 1999 [Refereed]
     
    We studied distribution, stand structure and transition of stand structure by altitude of a naturally regenerated Larix kaempferi stand on Mt. Komagatake, a volcano on the island of Hokkaido. L. kaempferi dominated at altitudes from 200 to 1,000 m above sea level, although broadleaved trees dominated at the foot of the mountain. The stands on the mountain were composed of L. kaempferi, Betula spp., and Populus maximowiczii, and asortment of others. At 500 m a. s l., the stand dominant height was 2.0 to 6.1 m and basal area at ground level was 0.1 to 7.8 m2/ ha. These values indicate that the stand had intensively restricted growth. The stands at higher altitudes were less developed than at lower altitudes in dominant height and basal area at ground level. The present L. kaempferi gradually started being established in the area between 500 to 700 m a. s. l. during 20 to 50 years after the eruption in 1929. Thereafter the number of the established L. kaempferi increased remarkably. We believed that seed dispersal from artificial forests of L. kaempferi that have been planted since 20 years after the eruption, and from the individuals that had invaded the stands in the very early period, contributed to the increase of naturally regenerated L. kaempferi trees.
  • 真駒内川における微細砂堆積と付着藻類の現存量に関する研究
    山田浩之, 中村太士
    日本林学会北海道支部論文集 48 136 - 138 1999 [Refereed][Not invited]
  • 中村 太士
    山林 大日本山林会 1375 (1375) 2 - 9 0487-2150 1998/12 [Not refereed][Not invited]
  • 緑の回廊を考える.
    中村太士
    フロント(水の文化情報誌) (5) 20 - 22 1998 [Not refereed][Not invited]
  • 予測できない生態系の応答を前提とした新たな管理指針−Adaptive Management (適応可能な管理) の必要性−.
    中村太士
    河川 (11) 57 - 63 1998 [Not refereed][Not invited]
  • 流域の視点から河川環境を考える.
    中村太士
    土木学会誌 (83) 37 - 39 1998 [Refereed][Not invited]
  • Yajima Takashi, Nakamura Futoshi, Shimizu Osamu, Shibuya Masato
    Research bulletins of the College Experiment Forests, Hokkaido University 北海道大学 55 (1) 216 - 228 0367-6129 1998 [Refereed][Not invited]
  • Ooishi Tomoko, Kikuchi Shun-ichi, Yajima Takashi, Shimizu Osamu, Nakamura Futoshi
    Research bulletins of the College Experiment Forests, Hokkaido University 北海道大学 55 (2) 349 - 368 0367-6129 1998 [Refereed][Not invited]
  • Application of landscape ecology to watershed management-How can we restore ecological functions in fragmented landscape ? -
    Nakamura, F
    Korean J.Ecol 21 (4) 373 - 382 1998 [Refereed][Not invited]
  • F Nakamura, T Yajima, S Kikuchi
    PLANT ECOLOGY 133 (2) 209 - 219 1385-0237 1997/12 [Refereed][Not invited]
     
    The structure and composition of riparian forests were examined along the Tokachi River, northern Japan. Both the hydrogeomorphic gradient and the temporal gradient were analyzed in attempt to explain the present pattern of riparian forests. The stability of floodplain surfaces was estimated on the basis of the elevation above the riverbed and the distance from the river channel. The characteristics of the substratum on which trees were established were also examined by excavation of buried sediment. The results indicated that soil moisture and organic content increased while the size of particles in the substratum decreased with increased elevation and distance from the river channel. Gradient analysis was employed to examine the distribution of dominant species, such as Alnus hirsuta, Toisusu urbaniana, Populus maximowiczii, Picea jezoensis and Abies sachalinensis. The relative dominance of each could be arrayed across the elevation gradient. Although the three broad-leaved pioneers dominated bars and floodplains near the river channel, their modes shifted from lower to higher elevation and amplitudes of distribution curves decreased in the following order: A. hirsuta, T. urbaniana, P. maximowiczii and conifers, which were located on the highest floodplains. Sites could be divided into three classes in terms of stability. There were fewer species at active sites, which favored the three pioneer species, but species richness and diversity increased with stand age. Semi-active and stable sites were more diverse with the establishment of conifers and other broad-leaved trees, which included upland species. However, species richness peaked and then decreased after trees reached 50 to 60 years of age. The growth of dwarf bamboo and the development of conifer-dominant stands impeded the establishment of other species, thereby reducing species richness and diversity in mature stands. Chronologically, floodplains could be differentiated into high-and low-frequency zones of flood disturbance, with pioneer species occupying the former, and late successional species found largely in the latter.
  • K Yoshida, S Kikuchi, F Nakamura, M Noda
    GEOMORPHOLOGY 20 (1-2) 135 - 145 0169-555X 1997/09 [Refereed][Not invited]
     
    Abies sachalinensis dominates the alluvial fan head of the Ochiushinai Gully on Rishiri Island, Japan. This species is able to adapt to frequent disturbances by debris flows. Even-aged stands composed of A. sachalinensis or Alnus maximowiczii were found along the channel, and standing dead trees buried by debris flows were discovered at the alluvial fan head. We used dendrochronological data in order to analyse the geomorphic history of the fan head. We determined the master ring-width chronology by synchronizing ring-width variations in living trees. This master chronology was used to cross-date the establishment and death of the buried trees. Results indicated that most of the buried trees were established in the 1870s and died in the early 1950s. Further, debris flow was estimated to have occurred in the 1890s and the late 1960s based upon the distribution of even-aged stands seen in aerial photos. The ring-width variations of the trees adjacent to the channel indicate a low correlation for synchronization, while those located on the hillslope have a high correlation. A low correlation in the riparian trees can be attributed to the instability of geomorphic surfaces caused by debris flow disturbances.
  • M Inoue, S Nakano, F Nakamura
    CANADIAN JOURNAL OF FISHERIES AND AQUATIC SCIENCES 54 (6) 1331 - 1341 0706-652X 1997/06 [Refereed][Not invited]
     
    Relationships between abundance of juvenile masu salmon (Oncorhynchus masou) and stream habitat were analyzed on two spatial scales, stream reach and channel unit, in northern Hokkaido, Japan. Reach-scale analyses revealed that high water temperatures limited the salmon population level and that the salmon abundance increased with cover availability. These two limiting factors were strongly associated with the presence of riparian forest, emphasizing its importance for the salmon population. Channel-unit scale analyses showed greater use of pools by the salmon, with greater depth and abundant cover underlying the patterns of habitat use. However, the relative importance of depth and cover varied among the reach types having different cover availability. In reaches that had abundant cover, cover itself was less important in determining patterns of habitat use within the reaches. In contrast, in reaches with poor cover, patterns of habitat use were strongly affected by cover. The results indicated that habitat characteristics at the reach scale affect not only the salmon abundance of the stream reaches, but also the determinants of local abundance patterns of the salmon within the reaches. It was suggested that larger-scale influences in a hierarchy of habitat scales should be considered for better understanding of fish-habitat relationships.
  • F Nakamura, T Sudo, S Kameyama, M Jitsu
    GEOMORPHOLOGY 18 (3-4) 279 - 289 0169-555X 1997/03 [Refereed][Not invited]
     
    The effects of wetlands on hydrology, water quality, and wildlife habitat are internationally recognized. Protecting the remaining wetlands is one of the most important environmental issues in many countries. However wetlands in Japan have been gradually shrinking due to agricultural development and urbanization, which generally lowers the groundwater level and introduces suspended sediment and sediment-associated nutrients into wetlands. We examined the influences of channelization on discharge of suspended sediment and wetland vegetation in Hokkaido, northern Japan. The impact of river channelization was confirmed not only by the sediment budgets but also by river aggradation or degradation after the channelization and by the resultant vegetational changes. The budgets of suspended sediment demonstrated that wash load was the predominant component accounting for 95% of the total suspended load delivered into the wetland. This suspended sediment was primarily transported into the wetland by flooding associated with heavy rainfall. Twenty-three percent of the wash load and 63% of the suspended bed material load were deposited in the channelized reach, which produced aggradation of about 2 m at the end of the reach. A shorting of the length of the channel, due to channelization of a meandering river, steepened the slope and enhanced the stream power to transport sediment. This steepening shifted the depositional zones of fine sediment 5 km downstream and aggraded the riverbed. Development of the watershed may increase not only the water discharge but also the amount of suspended sediments. The aggradation reduced the carrying capacity of the channel and caused sediment ladened water to flood over the wetlands. The fine sediment accumulated on the wetlands gradually altered the edaphic conditions and wetland vegetation. A low percentage (10 to 15%) of organic contents of wetlands' soil is more evidence indicating that the present condition is far different from normal. Original vegetation such as sedges and Alnus japonica were disappearing from the adjacent areas of the river channel and were being replaced by willow trees (Salix spp.).
  • 中村太士
    野生生物保護学会会報「ワイルドライフ・フォーラム」 2 (4) 101 - 111 1997 [Refereed][Not invited]
  • 流域の土地利用と河川環境のつながり−水辺域の構造と機能の回復をめざして−
    中村太士
    世界河川会議論文集 2-34 (2-40) 1997 [Refereed][Not invited]
  • 森と川と人
    中村太士
    森林科学 (2) 69 - 73 1997 [Refereed][Not invited]
  • 水辺林−その仕組みと役割−河川におよぼす働き
    中村太士
    グリーンパワー (2) 36 - 37 1997 [Not refereed][Not invited]
  • 水辺林−その仕組みと役割−欧米における保全と管理
    中村太士
    グリーンパワー (5) 36 - 37 1997 [Not refereed][Not invited]
  • 水辺林の保全に向けて−研究の現状と課題−
    中村太士
    林業技術 (8) 2 - 6 1997 [Not refereed][Not invited]
  • Sachiho Sugimoto, Futoshi Nakamura, Akiko Ito
    Journal of Forest Research 2 (2) 103 - 107 1341-6979 1997 [Refereed][Not invited]
     
    Riparian forests greatly influence aquatic ecosystems by providing shade cover, which controls water temperature and limits primary production. We examined the relationship between forest cover and summer stream temperature in northernmost Japan. Heat budget and statistical analyses were employed and the results were compared. Heat budget analysis revealed that the water temperature would decrease almost linearly from 29°C to 25°C with an increase in forested reaches along a 3.2 km stretch of the river. Multiple regression analysis by the stepwise method chose only open channel length as a variable to explain the variation in maximum stream temperature. A sharp increase in stream temperature was noted when riparian forest cover was removed in short lengths, of up to 1.0 km this increasing trend gradually flattened as the length of open stretch increased. Thus, even small openings in the riparian canopy resulted in drastic rises in summer stream temperature. The maximum summer temperatures estimated by the two methods were coincided, and can therefore be accurately estimated by regression analysis. Retrospective analysis based on the regression equation showed that the maximum summer temperature in 1947 was 6°C lower than at present, and that a sharp increase occurred from 1947 to 1960, a period of rapid expansion of agricultural land development in the watershed.
  • F Nakamura, S Kikuchi
    GEOMORPHOLOGY 16 (2) 139 - 145 0169-555X 1996/06 [Refereed][Not invited]
     
    Floodplain areas are primary storage sites for river sediment. In the Saru River, ages of floodplain surfaces were examined by tree ring analysis, and vertical and horizontal configurations of floodplain deposits were measured by field and aerial-photo surveying. A flood in 1992 provided a good opportunity to examine depositional and erosional processes of floodplain sediment before and after the flood. Predominant disturbances were observed in the unconstrained, wide reaches where floodplains develop. This event indicated that eroded areas of floodplain deposits in each age class linearly increased with sediment volume and that the proportion of the total area eroded decreased exponentially with increase in the age of sediment. We constructed basic equations expressing continuity of age distribution in order to analyze river sedimentation in a time series according to the results of the 1992 flood. The floodplain disturbance rates determined by this analysis showed similar temporal changes with sediment transport rates monitored at the Iwachishi Reservoir. A sharp increase in sediment discharge was seen after 1962 associated with the historical maximum rainfall in the temporal analysis of floodplain sediment. The time series approach presented here is useful for evaluating the speed of sediment waves and the cumulative impact of sedimentation in a river basin.
  • 有賀 誠, 中村太士, 菊池俊一, 矢島 崇
    日本林学会誌 78 (4) 354 - 362 1996 [Refereed][Not invited]
  • 阿部俊夫, 中村太士
    日本林学会誌 78 (1) 36 - 42 1996 [Refereed][Not invited]
  • 中村 太士
    森林科学 日本森林学会 18 57 - 58 1996
  • M. Aruga, F. Nakamura, S. Kikuchi, T. Yajima
    Nihon Ringakkai Shi/Journal of the Japanese Forestry Society 78 (4) 354 - 362 0021-485X 1996 [Refereed]
     
    Composition and structure of floodplain forests were compared with those of toeslope forests with special reference to site conditions. Site conditions at riparian zone are mainly created by frequent floods, whereas hillslope forests are disturbed rarely by shallow landslides. Floodplain forests indicate a high species richness as they locate away from the active channel, whereas toeslope forests exhibit a relatively uniform, high value of the species richness. Forest stands were classified into three groups by cluster analysis on the basis of the similarity index calculated from basal area of each species. This dendrogram represented two types of floodplain forests and one type of toeslope forests. Site conditions of both forests were significantly different. Floodplain forests showed a wide range of variance in mean particle size, and low water and organic contents in the soil. We applied the principal components analysis to synthesize a number of site variables. The first principal component (PC 1) was mainly formed by the mean particle diameter, water content and organic content, indicating 40% of contribution. The site conditions expressed by the PC 1 and stability index were clearly different depending on the three forest groups. We concluded that the variety in frequency and intensity of flood disturbances is responsible for creating heterogeneous habitat conditions for forest establishment, which results in a patchy mosaic pattern of floodplain forests in a narrow riparian zone.
  • T. Abe, F. Nakamura
    Nihon Ringakkai Shi/Journal of the Japanese Forestry Society 78 (1) 36 - 42 0021-485X 1996 [Refereed]
     
    Effects of coarse woody debris (CWD) on pool and cover formation were investigated along a small, meandering, low-gradient stream in northern Hokkaido, Japan. The riparian forest consisted of Salix spp. and Alnus hirsuta TURCZ ranging from 15 to 20 m in height. Regarding source and supply processes, 78% of the volume of the CWD was produced by bank erosion. The CWD pieces creating pools or cover were thicker, longer, and more perpendicular to the channel than other pieces. The untransported CWD pieces tended to be thicker, longer, more perpendicular, and less decayed, and therefore, create more pools and cover than fluvially transported pieces. This indicates that larger pieces particularly are important because they resist being transported by anchoring their ends to stream banks, and hence predominantly create pools or cover. Pool volume and cover area increased with increases in the amount of CWD and channel sinuosity. CWD was responsible for creating 38% of the total pool volume and 49% of the total cover area. These results indicate that CWD plays important roles in creating habitat structures for aquatic organisms in a stream.
  • 中村 太士, 亀山 哲, 實 三英子
    国際景観生態学会日本支部会報 日本景観生態学会 3 (2) 25 - 26 1345-532X 1996 [Refereed][Not invited]
  • F NAKAMURA, H MAITA, T ARAYA
    EARTH SURFACE PROCESSES AND LANDFORMS 20 (4) 333 - 346 0197-9337 1995/06 [Refereed][Not invited]
     
    Recent studies of sediment delivery and budgets in the United States indicate that upland erosion rates at a given time may not explain contemporaneous sediment yields from a drainage basin. This suggests temporal discontinuities in sediment delivery associated with hillslope and channel storage processes. Integration of sediment production, storage and transport is essential to understand sediment routing in basins. We analysed each process chronologically using aerial photographs, monitoring data of sediment movement and annual tree-rings, and then compared estimated temporal changes in sediment production from hillslopes, floodplain disturbance areas and sediment transport in river channels. Toeslopes, floodplains and alluvial fans together contained 59 per cent of sediment eroded from uplands over the last 30 years. Monitoring results of riverbed changes showed that the volume of stored sediment on floodplains decreased exponentially with succeeding floods. The age distribution of floodplain deposits reflected the disturbance history of a river channel, and followed an exponential decrease with age. The results of this study may have important implications for sediment control plans for watersheds in steep regions.
  • Speed of sediment wave in the Saru River estimated by age distribution of sediment.
    Nakamura, F, Kikuchi, S, Araya T
    Proc. International Sabo Sympo., Tokyo, Japan 495 - 502 1995 [Refereed][Not invited]
  • 渓畔域における森林と河川の相互作用
    中村太士
    「渓畔域の生態的構造と機能−森林と河川の相互作用−」森林科学 (13) 65 - 67 1995 [Refereed][Not invited]
  • 中村太士
    現代林業 11 (11) 24 - 31 1995 [Not refereed][Not invited]
  • NAKAMURA Futoshi
    JAPANESE JOURNAL OF ECOLOGY 一般社団法人 日本生態学会 45 (45) 295 - 300 0021-5007 1995 [Refereed][Not invited]
  • 緑の砂防−流域における土砂動態と河畔域の保全−.
    中村太士
    水工学シリーズ95-A-7.土木学会 A (7) 1 - 20 1995 [Not refereed][Not invited]
  • SAKIO Hitoshi, NAKAMURA Futoshi, OSHIMA Yasuyuki
    JAPANESE JOURNAL OF ECOLOGY 一般社団法人 日本生態学会 45 (45) 291 - 294 0021-5007 1995 [Refereed][Not invited]
  • SAITO Masami, ARAYA Tohru, NAKAMURA Futoshi
    Sabo Gakkaishi 社団法人 砂防学会 47 (6) 28 - 33 0286-8385 1995 [Refereed][Not invited]
     
    On July 12 in 1993, an earthquake (magnitude 7. 8) occurred at a depth of 34 km, off the shore of southwest Hokkaido. Weather Bureau (1993) named it "Hokkaido-nanseioki earthquake". It triggered many landslides over the southwest Hokkaido district. Especially, the Okushiri Island experienced numerous landslidings. Sediment produced by landslides still remains at footslopes, and might be re-mobilized by debris flow.
    We clarified general characteristics of landslides by this earthquake, and estimated sediment volume remaining on hillslopes of the landslides in each watershed of the Okushiri Island. The results are as follows;
    1. The number of earthquake-induced landslides recognized by aerial-photographs was 997 including 336 recurring landslides and 71 landslides occurring around roadcuttings or dam sites. Areal ratio of landslides to the distribution area was 0. 74 %, which is the average ratio in comparison with the previous earthquakes in Japan.
    2 . Landslides could be classified into 4 types, such as rock-fall, rock-slide, shallow soil-slide and debrisavalanche. Especially, debris-avalanche initiated by this earthquake was rarely observed as opposed to rainfall-induced landslides.
    3. Most landslides occurred at convex slopes cross-sectionally such as ridges, terrace cliffs and break lines of slopes.
    4, We estimated sediment volume left on hillslopes after landsliding. It was predominantly higher than rainfall-triggered cases. This remaining sediment is hazardous as secondary source for succeeding mass movements from the disaster-prevention point of view.
  • 坂本知己, 土屋俊幸, 佐野 真, 中村太士, 梶 光一, 伊藤晶子
    日本林学会誌 77 55 - 65 1995 [Refereed][Not invited]
  • F. Nakamura
    Transactions - Japanese Geomorphological Union 16 (3) 237 - 256 1995 [Refereed][Not invited]
     
    This paper describes the ecological structure and function of riparian zone which vary with spatial scale. The functions discussed are attenuation of sunlight energy, input of leaves and needles, contribution of woody debris to streams, and retention of flowing material out of transport. These primary functions directly or indirectly influence water and sediment qualities of streams, bars and floodplains. The new river management policy should emphasize the ecological functions of the riparian zone. The author proposes river restoration planning by preserving or creating landscape elements based on the concepts of sustaining physical and ecological linkages. -Author
  • F. Nakamura, Y. Ono
    Transactions - Japanese Geomorphological Union 16 (3) 193 - 194 1995 [Refereed]
     
    This special issue carries five papers presented at the JGU Symposium on "Landscape structure and Geomorphology' held on October 6, 1994 in Hokkaido University, on the occasion of the 1994 Autumn Meeting of JGU. -English summary
  • T. Sakamoto, T. Tsuchiya, M. Sano, F. Nakamura, A. Ito
    Nihon Ringakkai Shi/Journal of the Japanese Forestry Society 77 (1) 55 - 65 0021-485X 1995 [Refereed]
     
    The objective of our work is to synthesize several viewpoints on forest management, such as land conservation, wildlife, recreation, and timber production. This synthesis is necessary for developing multiple use of a forest. For that objective, we use the “landscape concept.” According to this concept, a landscape is a set of components which are organized in a hierarchy. First, we clarify the components from each different viewpoint, along with their spatial scales. Using a model region, we show examples where a few components having different viewpoints overlap each other. Even if such overlaps occur however, expected conflicts are avoidable if there are wide differences in the spatial scales between them. We discuss how, where conflicts cannot be avoided on the basis of spatial scales, a matrix arrangement similar to Clawson’s matrix is useful. These processes provide a new perspective in planning for forest management. © 1995, THE JAPANESE FORESTRY SOCIETY. All rights reserved.
  • F NAKAMURA, FJ SWANSON
    CANADIAN JOURNAL OF FOREST RESEARCH-REVUE CANADIENNE DE RECHERCHE FORESTIERE 24 (12) 2395 - 2403 0045-5067 1994/12 [Refereed][Not invited]
     
    The distribution of coarse woody debris in a fifth-order Cascade Range (Oregon) stream system was examined from a geomorphic point of view. The number, volume, location, orientation, decay class, and pool formation roles of coarse woody debris were investigated. The processes of coarse woody debris production, transport, and storage, which vary with channel and valley floor geomorphology, are responsible for the pattern of coarse woody debris distribution on valley floors. Channel width and sinuosity are the main factors that control production, storage sites, and hydrologic effects of coarse woody debris. The amount of coarse woody debris and the number of pool-forming pieces are relatively high in wide, sinuous reaches, where a complex structure of floodplains and riparian forests develops in association with a braided channel pattern. These relations are transferable to other systems with similar relations of coarse woody debris piece length to channel width.
  • 北海道の山地流域における斜面変動と河床変動の時系列解析.
    新谷融, 中村太士, 清水収, 菊池俊一
    「砂防計画の基本土砂量に関する研究:平成5年度報告」(社)砂防学会, JSECE Pub. (14) 9 - 17 1994 [Refereed][Not invited]
  • 北海道地域の土砂動態特性と水系砂防計画.
    新谷融, 中村太士, 清水収, 菊池俊一
    第26回(社砂防学会シンポジウム講演集「土砂災害の地域特性と砂防計画−砂防計画の時・空間スケールを考える−」(社)砂防学会, JSECE Pub. (13) 83 - 98 1994 [Not refereed][Not invited]
  • ランドスケープ概念による流域管理計画の策定
    坂本知己, 佐野 真, 土屋俊幸, 梶 光一, 中村太士, 伊藤晶子
    平成6年度研究成果選集,森林総合研究所 22 - 23 1994 [Refereed][Not invited]
  • 眞板秀二, 丸谷知己, 中村太士
    砂防学会誌(新砂防) 46 (5) 19 - 28 1994 [Refereed][Not invited]
  • 知床国有林の伐採が林分動態に与えた影響 -伐採5年後の林相と更新-
    菊池俊一, 矢島 崇, 中村太士, 清水 収, 沢井 理, 清野 年
    北海道大学農学部演習林研究報告 51 (1) 179 - 205 1994 [Refereed][Not invited]
  • 伊藤晶子, 中村太士
    日本林学会誌 76 160 - 171 1994 [Refereed][Not invited]
  • ITO Satoshi, NAKAMURA Futoshi
    Japanese Journal of Forest Environment 森林立地学会 36 (2) 31 - 40 0388-8673 1994 [Refereed][Not invited]
     
    Disturbance by various types of earth surface movement are characterized from a viewpoint of vegetation recovery to clarify their roles in forest dynamics. The earth surface movement refers to erosional processes and mass movement such as debris flow, landslide etc., which provide heterogeneous habitats consisting of several scoured (or denudation) and deposited zones. These scoured (or denudation) and deposited zones are the principal components of the earth surface movement to explain vegetation patterns and species diversity of forests. The disturbance intensity by earth surface movement can be graded from the forest floor less intensive to the conopy layer intensive. The effects of earth suface movement on modification of forest structure or promotion of regeneration habitats vary according to its intensity. We compared the disturbance by the earth surface movement with the other types of disturbance and generalized their roles in forest dynamics, by evaluating their effects based on the following three aspects: 1) physical intensity of destruction, 2) environmental changes for tree growth and recovery, and 3) modification of the succeeding disturbance regime. Variations in the effects of forest disturbance are one of the predominant factors controlling structural diversity such as species richness. Therefore, the wide ranges in size, intensity and degree of forest disturbance by the earth surface movement significaantly contribute to increase structural diversity. Further studies on spatio-temporal distribution of earth surface movement are needed to interpret long-term effects on dynamics and stability of forests.
  • 中村 太士
    国際景観生態学会日本支部会報 Japan Association for Landscape Ecology 2 (2) 1 - 2 1345-532X 1994
  • Ito Akiko, Nakamura Futoshi
    THE JOURNAL OF THE JAPANESE FORESTRY SOCIETY 76 (2) 160 - 171 0021-485X 1994 [Refereed]
     
    Synthesizing a wide range of natural resource management viewpoints into land use planning is a recent key-issue raised in forestry, agriculture, and river conservation fields. The objective of this paper is to show the basic concepts and framework of natural resource planning and management. The term of “natural resources” used here includes not only material resources such as timber, crops, and water, but also non-material resources such as traditional landscape and forest areas for soil and water conservation. For the past few decades, natural resources have been used from a single-purpose point of view. Rapid development in urban and rural areas after 1960 in Japan substantially deteriorated resource variability, which made the general public aware of the significance of natural resources as common property and of their environmental value. We propose the restriction of development to sustain natural resource diversity, which we believed to be a fundamental concept of management. Each resource requires different spatial and temporal extents for sustainable management. We clarify spatial scales of variable resources, and propose a hierarchical management scheme to maintain resource diversity. Furthermore, a temporal scale is discussed with respect to rotational land use which may sustain resource productivity. © 1994, THE JAPANESE FORESTRY SOCIETY. All rights reserved.
  • F NAKAMURA, FJ SWANSON
    EARTH SURFACE PROCESSES AND LANDFORMS 18 (1) 43 - 61 0197-9337 1993/02 [Refereed][Not invited]
     
    Effects of coarse woody debris (CWD) on channel morphology and sediment storage were investigated at five sites, representative of first-order to fifth-order streams. In the steep and bedrock-confined stream (first second order), interaction between the channel and CWD was limited, except where breakage upon falling produced CWD pieces shorter than channel width. Channel widening, steepening and sediment storage associated with CWD were observed predominantly in third- to fifth-order streams. Variation in channel width and gradient was regulated by CWD. In the fifth-order stream, most of the CWD pieces derived from the riparian forest interacted directly with the channel without being suspended by sideslopes. In this system CWD promoted lateral channel migration, but sediment storage was temporary, with annual release and capture.
  • 北海道地域における砂防計画の基本土砂量に関する研究
    新谷融, 中村太士, 清水収, 菊池俊一
    「砂防計画の基本土砂量に関する研究:平成4年度報告」 砂防学会誌(新砂防) 1993 [Refereed][Not invited]
  • ヨーロッパアルプス近自然工法と土地利用計画.
    中村太士
    砂防学会誌(新砂防) 46 (4) 52 - 53 1993 [Refereed][Not invited]
  • 中村太士
    水利科学 水利科学研究所 36 (209) 41 - 52 0039-4858 1993 [Refereed][Not invited]
  • 井上涼子, 中村太士
    水利科学 水利科学研究所 212 (3) 45 - 65 0039-4858 1993 [Refereed][Not invited]
  • 土地利用政策と林学の役割
    中村太士
    森林科学(日本林学会) (5) 5 - 10 1992 [Refereed][Not invited]
  • 河道内倒木・流木分布に関する河川地形的考察 −オレゴン州カスケイド山脈山地河川の事例−
    中村太士, フレデリック J, スワンソン
    第103回日本林学会大会発表論文集 577 - 579 1992 [Refereed][Not invited]
  • 景域保全学をめざして
    中村太士
    治山砂防と自然保護特集(?),北方林業 44 (7) 17 - 22 1992 [Refereed][Not invited]
  • 中村太士
    生物科学 日本生物科学者協会 44 (3) 128 - 140 0045-2033 1992 [Refereed][Not invited]
  • 中村太士
    砂防学会誌(新砂防) 45 (3) 29 - 37 1992 [Refereed][Not invited]
  • 中村太士
    砂防学会誌(新砂防) 砂防学会 45 (4) 15 - 21 0286-8385 1992 [Refereed][Not invited]
  • KIKUCHI Shunichi, ARAYA Tohru, SHIMIZU Osamu, NAKAMURA Futoshi
    Journal of the Japan Landslide Society The Japan Landslide Society 29 (3) 1 - 9 0285-2926 1992 [Refereed][Not invited]
     
    In general, landslide mass can be divided into small blocks depending upon their activities. The objective of this study is to clarify the historical movement of these blocks using dendrochronological analysis. Firstly, we investigated microtopography and inclination of trees (Abies sachalinensis) planted on gentle slope of the landslide. Secondly, we examined compression woods of tree rings formed in the inclined stems. In terms of compression wood, date of initiation, change in forming direction, and increase in areal extent are important factors to analyze historical movement of landslide.
    The landslide investigated is formed by two blocks which indicate different directions and histories of mass movement, although tree ring analysis clarified extensive movements from 1972 to 1973 and from 1986 to 1987 in both blocks. Ring samples in which compression woods are formed in different directions were found at the central area of each block, whereas samples showing extensive compression wood were found near the crack within each block. These results suggest frequent and complex movements in a small scale within a block.
  • The setting of erosion research and management in Japan and the western U.S. Proc.
    Swanson, F.J, F. Nakamura, G.E. Grant
    Japan-U.S. workshop on Snow Avalanche, Landslide, Debris Flow Prediction and Control, Tsukuba: 517 - 521 1991 [Refereed][Not invited]
  • 樽前火山・覚生唐沢源頭部における斜面侵食の季節変化
    宮縁育夫, 中村太士
    日本地形学連合学会誌(地形) 12 (4) 367 - 377 1991 [Refereed][Not invited]
  • Y. Miyabuchi, F. Nakamura
    Transactions - Japanese Geomorphological Union 12 (4) 367 - 377 1991 [Refereed]
     
    The objective of this study was to examine seasonal variation in erosion rates and grain size distribution of sediment produced from volcanic hillslopes. We sampled cliffs and talus slopes on the flanks of Tarumae Volcano, Hokkaido, northern Japan. Sediment production rates increased markedly (ten to a hundred times) when fluctuations of air temperature caused freeze-thaw cycles to detach particles from the soil mantle surface. Sediment production rates from volcanic hillslopes in subpolar zone are one to two orders of magnitude greater in fall to early winter than in the summer despite heavy rainfall. -from English summary
  • 土砂流出に与える砂防施設の効果
    中村太士
    「砂防施設の土砂流出に与える機能の解明に関する研究」平成元年度報告 (社) 砂防学会 51 - 57 1990 [Refereed][Not invited]
  • 中村太士
    「土砂災害データベースの現状と課題」新砂防(砂防学会誌) 43 (3) 32 - 34 1990 [Refereed][Not invited]
  • 中村太士
    生物科学 42 (2) 57 - 67 1990 [Refereed][Not invited]
  • 中村太士
    日本林学会誌 72 99 - 108 1990 [Refereed][Not invited]
  • 清水 収, 中村太士, 新谷融
    砂防学会誌(新砂防) 42 (6) 35 - 40 1990 [Refereed][Not invited]
  • Futoshi Nakamura
    Nihon Ringakkai Shi/Journal of the Japanese Forestry Society 72 (2) 99 - 108 0021-485X 1990 [Refereed]
     
    Sediment transported by episodic floods forms flood-plain deposits and remains for much longer periods of time such as decades or hundreds of years. The amount of sediment transported by a big flood may be fairly large in comparison with the volume transported by the ordinary stream flow. The objectives of this study were to clarify the characteristics existing in the temporal and spatial distribution of flood-plain deposits. Generally, the flood-plain deposits are stepped, and even-aged forests are established on these steps, which indicate discrete movement in magnitude and frequency. The sediment volume deposited on the flood-plain is determined by the river width which is limited by the proximity of adjacent hillsides. Therefore, large storages are predominantly observed in wide sections of a riverbed, and old sediment is mainly located at these places. Although the magnitude of sediment movements which occur historically are different, deposits are gradually decayed by successive floods. Generally, the total length of flood-plain deposits decreases with advancing in age, whereas the average height increases with age ; both relationships are expressed approximately by power functions. The average width of deposits does not change greatly with age. The residence time and erosion-rate of sediment were evaluated from the age-distribution of the total length, average width, and average depth of deposits. The validity of this analysis was confirmed by estimations from aerial photographs. © 1990, THE JAPANESE FORESTRY SOCIETY. All rights reserved.
  • 北海道における土砂災害.
    新谷融, 中村太士
    土質工学会誌(土と基礎) 37 (9) 53 - 58 1989 [Refereed][Not invited]
  • Nakamura Futoshi
    Journal of the Faculty of Agriculture, Hokkaido University 北海道大学 64 (1) 56 - 69 0018-344X 1989 [Refereed][Not invited]
  • 中村太士
    Research bulletin of the Hokkaido University Forests 北海道大学農学部演習林 46 (2) 287 - 313 0367-6129 1989 [Refereed][Not invited]
  • 中村太士, 百海琢司
    日本林学会誌 71 387 - 394 1989 [Refereed][Not invited]
  • 岡村俊邦, 中村太士
    水利科学 32 (6) 32 - 53 1989 [Refereed][Not invited]
  • Nakamura Futoshi, Dokai Takuji
    Nihon Ringakkai Shi/Journal of the Japanese Forestry Society 71 (10) 897 - 906 0021-485X 1989 [Refereed]
     
    Quantitatively because they greatly influence the biota in a stream, especially the fish. The factors used to estimate a heat budget were measured during the summer on the Horonai River which has a gentle bed-slope and a small discharge-rate. Sensible and latent heat had positive values during the day and night times which means that there was a plus energy-flux in the stream's water. The rate of daily solar-radiation in the open, which was seven times greater than that under the canopy, was the predominant factor in the heat budget. Changes in water temperature after the cutting of the riparian forest were estimated by assuming that all of the available solar-radiation could reach the surface of the stream. According to this analysis, water temperatures were estimated to increase by about 4°C as a daily maximum. From the comparison between this estimation and the daytime figures obtained under almost the same conditions of the net heat-budget on the water's surface during the defoliation period, the validity of the estimation of the increase in temperature was substantiated. The effect of riparian forest-cover on stream temperature decreases with an increase in stream width. The relationships between riparian tree-heights, crown diameters, and stream width are discussed, and approximate values of the influence of the stream width on the shading effect of forest canopies are presented. © 1989, THE JAPANESE FORESTRY SOCIETY. All rights reserved.
  • 中村太士
    Research bulletin of the Hokkaido University Forests 北海道大学農学部演習林 45 (1) 279 - 299 0367-6129 1988 [Refereed][Not invited]
  • 中村太士
    Research bulletin of the Hokkaido University Forests 北海道大学農学部演習林 45 (2) 301 - 369 0367-6129 1988 [Refereed][Not invited]
  • Influence of river channel morphology and sediment production on residence time and transport-distance
    Nakamura,F, Araya,T, Higashi,S
    Publication of International Association of Hydrological Sciences 165 355 - 364 1987 [Refereed][Not invited]
  • 河床堆積地の年代分布と滞留時間
    中村太士
    第97回日本林学会大会発表論文集 605 - 606 1986 [Refereed][Not invited]
  • NAKAMURA F
    Research bulletin of the Hokkaido University Forests 北海道大学演習林 43 (1) p1 - 26,図2p 0367-6129 1986 [Refereed][Not invited]
  • F. Nakamura
    Transactions - Japanese Geomorphological Union 7 (3) 165 - 184 1986 [Refereed][Not invited]
     
    Transport and storage processes of sediment in a river channel should be intergrated to construct a sediment budget. In this connection, even-aged forests supply chronological information on the movement of sediment to link both processes together. Sediment transport occurs as scouring and deposition take place alternately on a riverbed, and it results in the formation of waves. Assuming that a dominant wavelength found by a spectral analysis equals a transport-distance of sediment, the dominant wavelength is considered to be related to the width of river. The width that corresponds to the residence time determines the transport- distance that corresponds to residence time. The sediment in the lower reaches is hard to move; but once it moves, it is transported for a longer distance than in the upper reaches. -from Author
  • 斜面形態区分による侵食微地形の抽出手法.
    中村太士, 新谷 融, 東 三郎
    第96回日本林学会大会発表論文集 597 - 598 1985 [Refereed][Not invited]
  • Retardation of Debris Movement in Wider Place of River Channel.
    Nakamura,F, Araya,T, Higashi,S
    Proc. International Symposium on Erosion, Debris Flow and Disaster Prevention 127 - 132 1985 [Refereed][Not invited]
  • 中村 太士
    北海道大学農学部演習林研究報告 北海道大学演習林 42 (3) p525 - 536,図2p 0367-6129 1985 [Refereed][Not invited]
  • 東 三郎, 中村太士, 荻野 厚
    Research bulletin of the Hokkaido University Forests 北海道大学農学部演習林 42 (1) 109 - 132 0367-6129 1985 [Refereed][Not invited]
  • Nakamura Futoshi
    Research bulletins of the College Experiment Forests, Hokkaido University 北海道大学農学部演習林 42 (3) 525 - 536 0367-6129 1985 [Refereed][Not invited]
  • 中村太士, 新谷 融
    砂防学会誌(新砂防) 砂防学会 35 (3) 9 - 16 0286-8385 1983 [Refereed][Not invited]
  • 馬場仁志, 中村太士, 新谷 融
    砂防学会誌(新砂防) 砂防学会 36 (1) 8 - 16 0286-8385 1983 [Refereed][Not invited]

Books etc

  • 井上, 幹生, 中村, 太士, 講談社サイエンティフィク 
    講談社 2019/09 (ISBN: 9784065169995) x, 437p
  • 中村, 太士, 菊沢, 喜八郎 
    共立出版 2018/03 (ISBN: 9784320058194) xiv, 231p
  • 中村, 太士 
    Springer 2018 (ISBN: 9789811072024) ix, 263 p.
  • 北海道 水辺の生き物の不思議
    川井 唯史, 中村 太士 (Editor)
    北海道新聞社 2013/04
  • 川井, 唯史, 中村, 太士, 飯村, 幸代, 堀, 繁久, 池田, 幸資, 照井, 滋晴, 折戸, 聖, 粟倉, 輝彦, 針生, 勤, 片桐, 浩司, 山崎, 真実, 阿部, 豪, 山田, 浩行, 野中, 俊文, 田中, 一典 
    北海道新聞社 2013/04 (ISBN: 9784894536968) 207p
  • Panoramic View of the Life Science and Clinical Research Field(2013)
    NAKAMURA Futoshi (Contributor3.6.3 植物生理・生態)
    2013/03
  • 高等学校用 森林科学
    中村 太士 (Editor)
    実教出版株式会社 2013/01
  • NAKAMURA Futoshi (Editor)
    講談社 2013/01 (ISBN: 9784061552326) xii, 354p
  • 中村, 太士 
    技報堂出版 2011/03 (ISBN: 9784765534468) xi, 260p
  • 北海道の森林(分担:北方森林学会編)
    中村 太士 (Contributor生態系のつながり)
    北海道新聞社 2011
  • 川の蛇行復元−水理・物質循環・生態系からの評価−.
    中村太士 
    技報堂出版 2011 
    単著
  • 川の蛇行復元-水理・物質循環・生態系からの評価-.
    技報堂出版 2011
  • 日本の河川−標津川、釧路川. 図説「日本の河川」
    中村太士 (Contributor)
    朝倉書店 2010 
    共著
  • 日本の河川-標津川、釧路川. 図説「日本の河川」
    朝倉書店 2010
  • 景観生態学の展開.森への働きかけ
    海青社 2010
  • 中村, 太士, 柿沢, 宏昭 
    北海道大学出版会 2009/03 (ISBN: 9784832981898) xviii, 150p
  • 森林のはたらきを評価する−市民による森づくりに向けて−.
    中村太士, 柿澤宏昭 
    北海道大学出版会 2009 
    編著
  • 森林のはたらきを評価する-市民による森づくりに向けて-.
    北海道大学出版会 2009
  • 河川環境目標検討委員会, 中村, 太士, 辻本, 哲郎, 天野, 邦彦 
    技報堂出版 2008/07 (ISBN: 9784765534314) ix, 122p
  • 川の環境目標を考える −川の健康診断−
    中村太士, 辻本哲郎, 天野邦彦 (Supervisor)
    技報堂出版 2008 
    監修書
  • Gravel-Bed Rivers 6 ? From process understanding to river restoration
    Nakamura, F, Kawaguchi, Y, Nakano, D, Yamada, H (ContributorEcological responses to anthropogenic alterations of gravel-bed rivers in Japan, from floodplain river segments to the microhabitat scale)
    Elsevier Science Ltd 2008 
    共著
  • エコロジストの時間(日本環境アセスメント協会編)
    中村太士 (Contributorどうしたら自然再生事業は日本に根づくのか)
    東海大学出版会 2008 
    共著
  • Gravel-Bed Rivers 6 – From process understanding to river restoration
    Elsevier Science Ltd 2008
  • 北海道の森林(分担:辻井達一・岡田操・高田雅之編)
    中村 太士 (Contributor川の蛇行化)
    北海道新聞社 2007
  • 北海道の湿原
    中村太士 (Contributor川の蛇行化)
    北海道新聞社 2007 
    共著
  • よみがえれ自然−自然再生ガイドライン
    中村太士 (Supervisor)
    環境コミュニケーションズ 2007 
    共著
  • Plant Disturbance Ecology
    Academic Press 2007
  • Braided Rivers
    Blackwell 2006
  • 中村, 太士, 小池, 孝良 
    朝倉書店 2005/09 (ISBN: 9784254470383) xiv, 218p
  • 森林の科学−森林生態系科学入門−
    中村太士, 小池孝良 
    朝倉書店 2005 
    共編著
  • 中村, 太士 
    [北海道大学大学院農学研究科] 2004/03 442p
  • 自然再生−釧路から始まる−
    環境省, 社, 自然環境共生技術協会 (Contributor釧路での実践から得られた教訓)
    ぎょうせい 2004 
    編著
  • 砂防用語集
    社)砂防学会 (Contributor生態環境)
    山海堂 2004 
    編著
  • Fishes and Forestry Worldwide Watershed Interactions and Management
    Blackwell 2004
  • 新領域土木工学ハンドブック
    池田駿介, 林良嗣, 嘉門雅史, 磯部雅彦, 川島一彦 (Contributor自然・生態システム「森林から河川−物理系と生態系」)
    朝倉書店 2003 
    共編著
  • 森林の百科
    井上真, 桜井尚武, 鈴木和夫, 富田文一郎, 中静透 (Contributor森林と河川の相互作用)
    朝倉書店 2003 
    共編著
  • The ecology and management of wood in world rivers
    Gregory, S. V, Boyer, K. L, Gurnell, A. M (Contributor)
    American Fisheries Society 2003 
    編著
  • 森林計画学
    木平勇吉 (Contributor1.2森林計画の時空間スケールと社会的背景,2.3森林の機能別保全のサブシステム)
    朝倉書店 2003 
    編著
  • 生態学事典
    巖佐庸, 松本忠夫, 菊沢喜八郎 (Contributor)
    共立出版 2003 
    共編著
  • River Flow 2002
    Bousmar & Zech (Contributor)
    Lisse, Netherlands ; Tokyo : A.A. Balkema, a member of Swets & Zeitlinger 2002 
    共編著
  • Global perspective in forest conservation and sustainable agriculture
    Takahashi J (Contributor)
    The organizing committee of OASERD 2002 
    編著
  • Geomorphic Processes and Riverine Habitat
    Dorava, J. M, Montgomery, D. R, Palcsak, B. B, Fitzpatrick, F. A (Contributor)
    AGU Water Science and Application 2001 
    共編著
  • 水辺林管理の手引き
    渓畔林研究会 (Contributor水辺林管理の基本理念)
    日本林業調査会 2001 
    編著
  • 流域動態の認識とその方法
    北大図書刊行会 2001
  • 水辺域管理−その理論・技術と実践−
    砂防学会編 (Contributor)
    古今書院 2000 
    編著
  • 里山を考える101のヒント
    日本林業技術協会 (Contributor渓流と森林)
    東京書籍 2000 
    編著
  • 中村, 太士 
    築地書館 1999/07 (ISBN: 4806711810) ix, 138p
  • 流域一貫−森と川と人のつながり−
    中村太士 
    築地書館 1999 
    単著
  • 水辺域ポイントブック−これからの管理と保全−
    砂防学会 (Contributor)
    古今書院 1999 
    編著
  • 渓流生態砂防学
    東大出版会 1999
  • 流域一貫-森と川と人のつながり-
    築地書館 1999
  • 中村, 太士 
    [北海道大学農学部] 1998/03 155p
  • 水辺環境の保全と地形学
    日本地形学連合 (Contributor河川の土砂動態と水辺域の生態学的機能)
    古今書院 1998 
    編著
  • 地震による斜面災害−1993〜1994年北海道三大地震から−
    地すべり学会北海道支部 (Contributor南西沖地震−斜面災害と生産土砂の動態−)
    北海道大学図書刊行会 1997 
    編著
  • 水辺林の再生と保全に向けて−米国国有林の管理指針と日本の取り組み
    渓畔林研究会 (Contributor「2章 水辺林の生態的機能」「3章 河川地形とともに変化する水辺林の機能」「4章 豊かな水辺林の再生をめざして−日本における取り組み−第1節 北海道における水辺林の管理」)
    日本林業調査会 1997 
    編著
  • 森林の百科事典
    太田猛彦, 北村昌美, 熊崎 実, 鈴木和夫, 須藤彰司, 只木良也, 藤森隆郎 (Contributor「景観生態学」 他)
    丸善 1996 
    編著
  • 森の木の不思議
    日本林業技術協会 (Contributor年輪は樹木の傷病記録)
    日本林業技術協会 1996 
    編著
  • 景相生態学 (ランドスケープ・エコロジー入門)
    朝倉書店 1996
  • 中村, 太士 
    [北海道大学農学部] 1995/07 218p

Conference Activities & Talks

  • 講演「生物多様性を地図化することの意義と展望」  [Not invited]
    中村 太士
    第8回GISコミュニティフォーラム/東京  2012/05
  • 生態系評価を地図化する試み  [Not invited]
    中村 太士
    特定非営利活動法人 地球環境カレッジ第112回定例講演会/東京  2012/04
  • パネルディスカッション:生物多様性を意識した今後の河川環境管理とは?  [Not invited]
    中村 太士
    応用生態工学会国際交流委員会 国際シンポジウム 生物多様性を意識した河川環境管理~COP10後の日本と欧州での取り組み~/応用生態工学会国際交流委員会/東京工業大学  2011/06
  • Panel Discussion: International Workshop on Habitatology for Linking Sediment Dynamism and Biodiversity  [Not invited]
    Scientific Research Project on Tagliamento River, NE Italy.  2011/06  (Kyoto, Japan)
  • 講演・自然再生でやるべきこと、やってはいけないこと-釧路湿原や知床の経験から-  [Not invited]
    中村 太士
    アポイ岳の自然再生学習会/アポイ岳再生委員会/様似町  2011/02
  • 基調講演「生態系のつながりと生物多様性:河川生態系に着目して」  [Not invited]
    中村 太士
    環境システム学部フォーラム 水と河川をめぐる多様性/酪農学園大学  2011/02
  • 基調講演「砂礫の移動様式の変化が流域生態系にもたらすインパクト~元気がなくなった日本の河川の現状と課題~」  [Not invited]
    中村 太士
    北海道淡水魚保護フォーラムNo.11in札幌 川底からの河川再生~もうひとつの河野流れ~  2011/01
  • 流域的視点からみた釧路湿原保護の現状と課題  [Not invited]
    第2回大会公開シンポジウム「自然保護区のあり方−人類と生物圏との共生に向けて−」  2011  野生生物保護学会
  • 流域における土地利用変遷と河川環境の変化  [Not invited]
    流域環境保全と市民参加 −市民・行政・研究者のネットワークづくり−  2011  東京農工大学農学部
  • 物質の流れと生物の生息場環境−釧路湿原を対象にして−  [Not invited]
    景観生態学の現状と将来−発展的展望から− 第46回日本生態学会(松本1999)自由式シンポジウム  2011  国際景観生態学会日本支部会
  • 北海道における自然復元の考え方と課題−釧路湿原の保全および標津川再蛇行化計画を事例として−  [Not invited]
    公開シンポジウム「河川の自然復元の現状と課題」  2011  応用生態工学研究会
  • オーガナイザー  [Not invited]
    パネルディスカッション生態分科会:水循環シンポジウム−21世紀の研究課題と展望−  2011  日本学術会議・メカニクス構造研究連絡委員会・水力学、水理学専門委員会・社会環境工学研究連絡委員会・水資源学専門委員会
  • 河川・水辺・湿地の復元 −物質の流れ・攪乱・生息場環境の視点から−  [Not invited]
    第7回応用生態工学会公開シンポジウム『川と川辺のリンケージ:健全な河川生態系を修復するために』  2011  応用生態工学会
  • 自然再生事業において保護区・再生優先区の抽出をいかに実施するか  [Not invited]
    2011  日本景観生態学会
  • 自然再生−地域(region),(catchment),地区(local site)における分析と復元の考え方  [Not invited]
    公開シンポジウム「自然再生をめぐる学術と技術の展望」  2011  日本緑化工学会
  • 北海道の川を蘇らせるには、今何をすべきか  [Not invited]
    兵庫県の河川自然再生コウノトリの舞う郷へ シンポジウム「川の自然再生を考える」日本景観生態学会第1回大会公開シンポジウム景観生態学と戦略的環境アセスメン  2011  兵庫県立人と自然の博物館・兵庫県県土整備部・応用生態工学会:応用生態工学会関連企画
  • 釧路湿原での自然再生:環境と社会・経済とのバランスをいかにとるか  [Not invited]
    兵庫県の河川自然再生コウノトリの舞う郷へ フォーラム「円山川の自然再生に関するフォーラム」  2011  国土交通省近畿地方整備局・兵庫県・豊岡市:応用生態工学会関連企画
  • 釧路湿原流域の現状と課題、そして再生の考え方  [Not invited]
    第7回日本生態学会公開講演会 L4 湿原の自然再生  2011  日本生態学会
  • 自然復元と順応的管理  [Not invited]
    共同利用シンポジウム  2011  東京大学海洋研究所
  • 自然再生−地域、流域、地区における分析と復元の考え方  [Not invited]
    環境修復セミナープログラム  2011  立正大学
  • 自然再生・森林復元の可能性と技法 コーディネーター  [Not invited]
    第116回日本森林学会公開シンポジウム  2011  日本森林学会
  • 地形変化に伴う生物生息場形成と生活史戦略−人為的影響とシステムの再生をめざして  [Not invited]
    創立25周年記念シンポジウム「地形学の新展開」  2011  日本地形学連合
  • 階層的河川環境評価の考え方  [Not invited]
    河川環境目標への科学的アプローチは可能か−考え方と実際−ワークショップ  2011  河川環境目標検討委員会 共催:応用生態工学会
  • 切り下げ(スリットを含む)の必要性と現状  [Not invited]
    渓流・河川横断構造物の切り下げ(スリットを含む)セミナー  2011  応用生態工学札幌・独立行政法人北海道開発土木研究所
  • 陸域・水域エコトーンにおける生物生息場形成と生活史戦略−人為的影響とシステムの再生をめざして−  [Not invited]
    第4回海域・陸域統合管理論セミナー  2011  京都大学フィールド科学教育研究センター
  • 河川環境を流域の視点から考える  [Not invited]
    公開シンポジウム「流域で見る洪水ハザード」  2011  名古屋大学(災害・防災学習カリキュラム開発委員会)
  • パネリスト  [Not invited]
    第2分科会「ふるさとみやぎの自然とひとをつなぐ水〜流域水循環系の健全化〜」  2011  第11回水シンポジウム2006 in みやぎ
  • 応用生態工学が担ってきた研究領域と未知の領域−現状認識と新たな視点の発掘をめざして−  [Not invited]
    応用生態工学の10年とこれから−土木工学と生態学の壁はとりのぞかれたか?  2011  応用生態工学10周年記念東京大会
  • 環境評価・復元の基本的な考え方−地域・流域・地区における診断と治療−  [Not invited]
    北海道の環境と農林水産−次世代への提言−  2011  日本水産学会北海道支部大会
  • 河川生態系を蘇らせる新たな視点  [Not invited]
    東北河川技術研修  2011  国土交通省 東北地方整備局
  • 生物環境をいかに捉えるか-工学と生態学の接点-  [Not invited]
    2011  神戸大学大学院工学研究科
  • 流域一貫~森林管理と流域保全~  [Not invited]
    中村 太士
    講演会/西条市  2010/10
  • 知床世界自然遺産 登録から5年間の歩みと未来  [Not invited]
    中村 太士
    知床世界自然遺産登録5周年記念シンポジウム/横浜ランドマークプラザ  2010/06
  • 「景観・生息場の保全」  [Not invited]
    中村 太士
    国際ワークショップ「生物多様性保全に向けた応用生態工学からのアプローチ」~COP10名古屋に向けて~ 名古屋国際会議場  2010/05
  • 魚の棲める川への自然再生  [Not invited]
    「川の自然生態系と在来魚を守る−知床を含む北海道の現状と将来−」  2010  2007年度魚類学会公開市民講座/北海道・淡水魚保護フォーラム
  • 流域の自然再生を考える  [Not invited]
    2010  応用生態工学会・日本生態学会東北地区会
  • 生態系管理の考え方と実践.  [Not invited]
    「生態系管理を考える」東京農工大学野生動物管理システム 公開シンポジウム  2010  東京農工大学
  • 河川・湿地の自然再生の技術. 「河川・湿地の自然再生の理念と記述」  [Not invited]
    第2回自然再生講習会  2010  日本生態学会
  • 生物環境をいかに捉えるか-工学と生態学の接点-  [Not invited]
    中村 太士
    特別講演 神戸大学工学部市民工学教室  2009/12
  • まっすぐな川・まがった川-蛇行した川の持つ意味  [Not invited]
    中村 太士
    標津川技術検討委員会成果発表会  2009/10
  • River and floodplain restoration in the US and Japan -Current accomplishment and problems,and future directions -/Hokkaido  [Not invited]
    中村 太士
    2009/10
  • 人と川そのつながり~ヤマメ湧く川は今~  [Not invited]
    中村 太士
    シンポジウム/旭川  2009/10
  • 公開シンポジウム 市民参加-理念と方法- 横浜市/丹沢大山自然再生委員会・市民参加研究会  [Not invited]
    中村 太士
    2009/04
  • 択伐は稚幼樹の成長量と生残率を向上させるか?  [Not invited]
    宮久史, 吉田俊也, 野口麻穂子, 安田哲, 中村太士
    日本森林学会  2009/03  京都大学
  • International Symposium on the 4 Major Rivers Ecological Conservation and Restoration/Korea  [Not invited]
    中村 太士
    2009/03
  • エゾアカガエルの陸上ハビタット利用‐夏季と秋季の比較‐  [Not invited]
    永美暢久, 赤坂卓美, 中村太士
    日本生態学会  2009/03  岩手県立大学
  • 北海道北部の択伐が実施された針広混交林における林冠ギャップ動態と稚樹の定着立地特性  [Not invited]
    宮久史, 吉田俊也, 野口麻穂子, 米康充, 小熊宏之, 坂井励, 高橋廣行, 小宮圭示, 小野貴司, 中村太士
    日本生態学会  2009/03
  • 総合環境科学のための野外トレーニングコースに関する国際ワークショップ/北海道大学  [Not invited]
    中村 太士
    2009/03
  • 「森林・水源環境保全・再生に向けて今求められる施策は何か」  [Not invited]
    中村 太士
    第6回水源環境保全・再生かながわ県民フォーラム  2009/02
  • 森と川と海−地球の生態を考える.  [Not invited]
    海浜美化フォーラム2009  2009  NPO法人 北海道海浜美化を進める会主催
  • しべつの森と川と生きものたち.  [Not invited]
    北大・東農大による研究活動報告会− コーディネーター  2009  標津町
  • 渓流環境モニタリングと情報整備.  [Not invited]
    自然環境保全センター公開講座「渓流環境モニタリングと情報整備」講演  2009
  • なぜ、川の周りには森は必要か?  [Not invited]
    別寒辺牛川地域連携講座「森と海をつなぐ川の環境をどう守るか」  2009  京都大学フィールド科学教育センター
  • Variations of fluvial export of large wood and sediment along the precipitation and latitude at the watershed scale  [Not invited]
    Futoshi Nakamura, Jung Il Seo・Alexander, K. Fremier
    American Geophysical Union  2008/12  The Moscone Center West Building, Howard Street, SanFrancisco, California, USA
  • Dynamic processes of large woody debris and their effects on fluvial export at the watershed scale  [Not invited]
    Jung Il Seo, Futoshi Nakamura, Kun Woo Chun
    American Geophysical Union  2008/12  The Moscone Center North Building, Howard Street, SanFrancisco, California, USA
  • 流域圏の防災・環境研究に果たす沿岸域フィールド・スタディの役割と展望  [Not invited]
    中村太士
    撹乱に伴う生物生息場形成と生活史戦略.平成20年度京都大学防災研究所附属流域災害研究センターシンポジウム  2008/11
  • 森林性両生類の繁殖場所選択と繁殖成功  [Not invited]
    永美暢久, 赤坂卓美, 中村太士
    日本森林学会北海道支部会  2008/11  札幌コンベンションセンター
  • 流域の自然再生を考える  [Not invited]
    中村太士
    応用生態工学、日本生態学会東北地区会  2008/11
  • 韓国山林庁基礎研究支援事業(新山地防災事業団)国際シンポジウム  [Not invited]
    中村 太士
    2008/10
  • Canopy gap dynamics and its influences on juvenile recruitments in a mixed forest under a selection system in northern Japan  [Not invited]
    Miya, H, Yoshida, T, Miya, H, Noguchi, M, Yone, Y, Oguma, H, Sakai, R, Takahashi, H, Komiya, K. Nakamura,F
    6th IUFRO 1.05 Workshop of "uneven-aged silviculture"  2008/10  静岡市
  • 「河川の構造と魚類の夏季生息場としての機能−蛇行河川における事例−」  [Not invited]
    永山滋也, 中村太士
    日本陸水学会第73回大会(札幌大会)  2008/10  札幌市
  • Scale-dependent controls on the fluvial export of large wood  [Not invited]
    Futoshi Nakamura
    International Symposium of Innovative Forest Disasters R&D Center  2008/10  Kangwon National University
  • Historical degradation of wetland and lake ecosystems associated with landuse development in Kushiro River catchment, northern Japan  [Not invited]
    Nakamura, F, Ahn Y.S
    The 5th Jpana-Korea-China International Workshop ? Present Earth Surface Processes and Historical Environmental Changes in East Asia  2008/10
  • 新山地防災事業団 国際シンポジウム講演  [Not invited]
    中村太士
    新山地防災事業団 国際シンポジウム  2008/10  韓国
  • 「河川改修に伴う魚類群集とその生息場の時空間変動−リバー・ランドスケープ・ユニットに着目して−」  [Not invited]
    永山滋也, 中村太士
    ELR2008福岡  2008/09  福岡
  • 農地景観において同所的に生息するコウモリ類3種のハビタット選択  [Not invited]
    赤坂卓美, 赤坂宗光, 中村太士
    ELR(日本緑化工学会・日本景観生態学会・応用生態工学会 三学会合同大会  2008/09  福岡
  • 農地帯の森林における樹洞木の分布およびエゾモモンガによる冬期のねぐら選択  [Not invited]
    勝又聖乃, 赤坂卓美, 中村太士
    ELR2008(応用生態工学会、日本景観生態学会、日本緑地工学会三学会合同大会)  2008/09  福岡
  • 広域の資源管理を目的とした植物生態系の種類数−面積曲線によるランドスケープの認識  [Not invited]
    森本淳子, 小野貴司, 中村太士
    ELR2008福岡,  2008/09  福岡
  • 香川県直島における野生ツツジ群落を活かした景観の保全  [Not invited]
    水本絵夢, 森本淳子, 中村太士
    ELR2008福岡  2008/09  福岡
  • Habitat selection of three sympatric Myotis species in agricultural landscape.  [Not invited]
    Akasaka, T, Nakamura, F
    Sustainability on Food, Feed, Fiber, Water, Energy: Science, Technologies, and Global Strategies  2008/06  札幌
  • 流域スケールにおける大型有機物片(倒流木)の生産・滞留過程と流出量の変化  [Not invited]
    徐 正一, 中村太士, 全 槿雨
    日本砂防学会  2008/05  北海道立道民活動センター(かでる2・7)
  • 自然再生に向けた県民参加と協働のあり方を考える.  [Not invited]
    2008  神奈川県自然環境保全センター
  • 北海道の森と川の再生.  [Not invited]
    大学との連携による森林づくり・地域づくりシンポジウム  2008  北海道大学大学院農学研究院、標津町
  • 森林・水源環境保全・再生に向けて今求められる施策は何か.  [Not invited]
    第6回水源環境保全・再生かながわ県民フォーラム「水源地・森林再生の第2ステージに向けて」 パネリスト  2008
  • 川の自然再生−知床世界自然遺産地域と標津川からの報告.  [Not invited]
    第1回河川環境管理財団 北海道事務所研究発表会基調講演  2008
  • 撹乱に伴う生物生息場形成と生活史戦略  [Not invited]
    シンポジウム「流域圏の防災・環境研究に果たす沿岸域フィールド・スタディの役割と展望」  2008  京都大学防災研究所附属流域災害研究センター
  • 大学との連携による森林づくり・地域づくりシンポジウム  [Not invited]
    中村太士
    2008
  • 第11回水源地生態研究セミナー  [Not invited]
    中村太士
    2008
  • 北海道洞爺湖サミット記念「国際交流森林環境フォーラム」  [Not invited]
    中村太士
    2008
  • 自然再生に向けた県民参加と協働のあり方を考える  [Not invited]
    中村太士
    2008
  • 森林の機能評価と協働による森づくり  [Not invited]
    中村 太士
    第22回 ニッセイ財団 助成研究ワークショップ/北海道大学  2007/12
  • 自然再生事業ガイドラインの概要  [Not invited]
    中村 太士
    (社)自然環境共生技術協会/公開シンポジウム よみがえれ自然~自然再生事業ガイドライン~ 東京  2007/11
  • Degradation and restoration of rivers and wetlands in Hokkaido, northern Japan  [Not invited]
    Futoshi Nakamura
    International Conference on Landscape and Ecological Engineering Issues and Problems for Environmental Restoration 2007  2007/11  Seoul National University
  • 魚の棲める川への自然再生.「川の自然生態系と在来魚を守る−知床を含む北海道の現状と将来−」  [Not invited]
    中村太士
    2007年度魚類学会公開市民講座/北海道・淡水魚保護フォーラム  2007/10
  • Rapid shrinkage of Kushiro Mire, the largest mire in Japan, due to increased sedimentation associated with land-use development in the catchment  [Not invited]
    Futoshi Nakamura
    GLP Symposium on "Impacts of Global Change on Vegetation and Cycling of Materials in Ecosystems"  2007/02
  • 自然再生事業における住民参加 −釧路湿原の事例を中心に−  [Not invited]
    (社)日本環境アセスメント協会第2回セミナー  2007
  • 地形変化に伴う生物生息場形成と生活史戦略  [Not invited]
    「河川工作物が生物生息環境に与える影響と課題」(講演)  2007  (財)北海道河川防災研究センター
  • 森と川と海、そして人のつながり  [Not invited]
    矢作川「川会議」  2007
  • 国土環境保全における治山の役割−過去、現在、そして未来−  [Not invited]
    「北海道民有林治山事業60周年記念講演会」  2007  (社)北海道治山林道協会
  • 北の大地での自然との共生  [Not invited]
    損保ジャパン札幌コールセンター開設記念「市民のための環境公開講座」(パネリスト)  2007  損保ジャパン
  • 自然を復元できるか  [Not invited]
    平成19年度 北海道大学公開講座「くらしを創る−安全と安心の科学」  2007
  • 川の自然再生技術に関する発展の方向性と壁.  [Not invited]
    2007  NPO法人 北海道魚道研究会
  • 自然再生ガイドラインの概要.  [Not invited]
    2007  (社)自然環境共生技術協会(NECTA)
  • 森林の機能評価と協働による森づくり.  [Not invited]
    (財)日本生命財団 助成研究ワークショップ  2007  (財)日本生命財団
  • NPO法人 北海道魚道研究会  [Not invited]
    中村太士
    2007
  • 平成19年度 北海道大学公開講座「くらしを創る−安全と安心の科学」  [Not invited]
    中村太士
    2007
  • 損保ジャパン札幌コールセンター開設記念「市民のための環境公開講座」(パネリスト)損保ジャパン  [Not invited]
    中村太士
    2007
  • 矢作川「川会議」  [Not invited]
    中村太士
    2007
  • 北海道民有林治山事業60周年記念講演会((社)北海道治山林道協会)  [Not invited]
    中村太士
    2007
  • 「河川工作物が生物生息環境に与える影響と課題」(講演)((財)北海道河川防災研究センター)  [Not invited]
    中村太士
    2007
  • (社)日本環境アセスメント協会第2回セミナー  [Not invited]
    中村太士
    2007
  • 環境評価・復元の基本的な考え方−地域・流域・地区における診断と治療−  [Not invited]
    中村太士
    日本水産学会北海道支部  2006/12
  • 応用生態工学が担ってきた研究領域と未知の領域−現状認識と新たな視点の発掘をめざして−  [Not invited]
    中村太士
    応用生態工学会  2006/10  東京
  • UNITAR/KIWC WORKSHOP ON BIODIVERSITY Ecosystem,Water and Biodiversity Organized jointly with the Kushiro International Wetland Centre(KIWC)  [Not invited]
    中村 太士
    UNITED NATIONS INSTITUTE FOR TRAINING AND RESEACH Hiroshima Office for Asia and the Pacific  2006/08
  • ふるさとみやぎの自然とひとをつなぐ水〜流域水循環系の健全化〜  [Not invited]
    中村太士
    (社)土木学会水工学委員会、国土交通省東北地方整備局、宮城県、  2006/08
  • 本来の川と取り戻すために−自然再生を拓く河床低下対策−  [Not invited]
    中村太士
    応用生態工学札幌,独立行政法人寒地土木研究所  2006/07
  • 河川環境を流域の視点から考える  [Not invited]
    中村太士
    災害・防災学習カリキュラム開発委員会  2006/04
  • 森林と河川の相互作用−過去と現在、そして再生へ向けた未来への展望  [Not invited]
    河川生態系連続講演会「流域生態系を育む河川ネットワーク」  2006  特定非営利活動法人 日本国際湿地保全連合
  • 21世紀のパイロットフォレストのあり方を探る〜カラマツ資源の持続的利用と環境との調和〜  [Not invited]
    パイロットフォレスト造成50周年記念シンポジウム(パネリスト)  2006  北海道森林管理局
  • パイロットフォレスト造成50周年記念シンポジウム(北海道森林管理局)  [Not invited]
    中村太士
    2006
  • 環境科学研究所生物研究連絡会((財)電力中央研究所)  [Not invited]
    中村太士
    2006
  • 河川生態系連続講演会「流域生態系を育む河川ネットワーク」特定非営利活動法人 日本国際湿地保全連合  [Not invited]
    中村太士
    2006
  • River alteration and its ecological consequences from reach to catchment scale  [Not invited]
    Futoshi Nakamura
    Gravel-Bed Rivers 6 ? From process understanding to river restoration  2005/09  AUSTRIA
  • 切り下げ(スリットを含む)の必要性と現状  [Not invited]
    中村太士
    応用生態工学札幌・独立行政法人北海道開発土木研究所  2005/08
  • 階層的河川環境評価の考え方  [Not invited]
    中村太士
    河川環境目標検討委員会 共催:応用生態工学会  2005/06
  • 地形変化に伴う生物生息場形成と生活史戦略−人為的影響とシステムの再生をめざして  [Not invited]
    中村太士
    日本地形学連合  2005/05
  • 自然再生・森林復元の可能性と技法  [Not invited]
    中村太士
    日本森林学会  2005/03
  • 自然再生−地域、流域、地区における分析と復元の考え方  [Not invited]
    中村太士
    立正大学環境修復セミナープログラム  2005/03
  • Current environmental problems and restoration efforts in the Kushiro Mire, the largest wetland in Japan.  [Not invited]
    Nakamura, F
    2005 World Wetlands Day Ceremony and Symposium.  2005/02  Changnyeong-gun, Korea
  • 自然再生事業と阿蘇草原再生  [Not invited]
    阿蘇くじゅう国立公園指定70周年記念−阿蘇草原再生シンポジウム  2005  環境省
  • 第6回「森林と河川の相互作用−過去と現在、そして再生へ向けた未来への展望−  [Not invited]
    河川生態系連続講演会 流域生態系を育む河川ネットワーク  2005  特定非営利活動法人 日本国際湿地保全連合
  • 階層的河川環境評価の考え方  [Not invited]
    河川環境目標への科学的アプローチは可能か−考え方と実際−  2005  河川環境目標検討委員会(国土交通省)
  • 河川環境目標検討委員会(国土交通省)  [Not invited]
    中村太士
    2005
  • 河川生態系連続講演会 流域生態系を育む河川ネットワーク(特定非営利活動法人日本国際湿地保全連合)  [Not invited]
    中村太士
    2005
  • 阿蘇くじゅう国立公園指定70周年記念−阿蘇草原再生シンポジウム(環境省)  [Not invited]
    中村太士
    2005
  • 自然復元と順応的管理  [Not invited]
    中村太士
    京大学海洋研究所 共同利用シンポジウム  2004/11
  • 釧路湿原流域の現状と課題、そして再生の考え方  [Not invited]
    中村太士
    日本生態学会  2004/08  釧路
  • 釧路湿原での自然再生  [Not invited]
    中村太士
    国土交通省近畿地方整備局・兵庫県・豊岡市:応用生態工学会関連企画  2004/08
  • 北海道の川を蘇らせるには、今何をすべきか  [Not invited]
    中村太士
    兵庫県立人と自然の博物館・兵庫県県土整備部・応用生態工学会:応用生態工学会関連企画  2004/08
  • 森林と河川の相互作用−物理化学系ならびに生態系の視点から−  [Not invited]
    中村太士
    土木学会 水工学委員会・海岸工学委員会  2004/07
  • 自然再生−地域(region),流域(catchment),地区(local site)における分析と修復の考え方  [Not invited]
    中村太士
    日本学術会議  2004/06  東京
  • 自然再生事業において保護区・再生優先区の抽出をいかに実施するか  [Not invited]
    中村太士
    日本景観生態学会  2004/03  広島
  • 自然再生の課題と展望  [Not invited]
    第2回「川の自然再生」セミナー  2004  財団法人リバーフロント整備センター
  • 自然再生事業の評価について  [Not invited]
    第1回シンポジウム 自然と共生する社会づくり −自然再生事業の実践的課題と展望−(パネルディスカッション)  2004  社団法人自然環境共生技術協会
  • 自然再生技術に関する発展の方向性と壁  [Not invited]
    第491回建設技術講習会テキスト(環境問題)  2004  社団法人全日本建設技術協会・北海道
  • 川のダイナミクスと連続性−ダム下流の環境変化に関連して−  [Not invited]
    コーディネーター第7回水源地生態研究セミナー  2004  ダム水源地環境整備センター
  • 川がもたらす湿原の環境  [Not invited]
    「ふれあい自然ワークショップ」環境講演会  2004  浜中町教育委員会
  • 森林と河川の相互作用 −物理化学系ならびに生態系の視点から−  [Not invited]
    2004年度(第40回)水工学に関する夏期研修会講義  2004  土木学会 水工学委員会・海岸工学委員会
  • 「ふれあい自然ワークショップ」環境講演会(浜中町教育委員会)  [Not invited]
    中村太士
    2004
  • 第491回建設技術講習会テキスト(環境問題):(社団法人全日本建設技術協会)  [Not invited]
    中村太士
    2004
  • 第1回シンポジウム 自然と共生する社会づくり −自然再生事業の実践的課題と展望−((社)自然環境共生技術協会)  [Not invited]
    中村太士
    2004
  • 第7回水源地生態研究セミナー(ダム水源地環境整備センター)  [Not invited]
    中村太士
    2004
  • 第2回「川の自然再生」セミナー(財団法人リバーフロント整備センター)  [Not invited]
    中村太士
    2004
  • 河川および湿原再生の原則と適用−釧路湿原ならびに標津川の再生事業から学んだ教訓−  [Not invited]
    中村太士
    第47回日本水環境学会セミナー  2003/11
  • 河川・水辺・湿地の復元−物質の流れ・撹乱・生息場環境の視点から−  [Not invited]
    中村太士
    応用生態工学会  2003/10  北九州市
  • Catchment management issues in Japan. "Sediment management in river systems: Basin scale approaches to predicting land to ocean responses"  [Not invited]
    Futoshi Nakamura
    International Workshop 12-14th February 2003  2003/02  Gisborne, Waipaoa River Basin,New Zealand
  • 森林の公益的機能の限界と可能性:森林の公益的機能の限界と可能性  [Not invited]
    2003  社団法人 北海道造林協会
  • 自然再生事業の調査計画論 −目標と評価の視点から−:自然環境共生技術フォーラム講演録  [Not invited]
    自然環境共生技術フォーラム  2003
  • 釧路湿原の現状と流域保全・再生への提言  [Not invited]
    釧路湿原自然再生大会  2003  釧路湿原自然再生大会実行委員会
  • 川の自然再生の考え方−その原則と適用−:「川の自然再生」セミナーテキスト::  [Not invited]
    2003  財団法人リバーフロント整備センター
  • 森と川の変貌と自然再生  [Not invited]
    全国湖沼河川養殖研究会第76回大会福井県(話題提供)  2003
  • 河川および湿原再生の原則と適用 −釧路湿原ならびに標津川の再生事業から学んだ教訓−  [Not invited]
    第47回日本水環境学会セミナー 自然再生推進・生態系保全ーその実践ならびに評価手法を考えるー  2003  社団法人日本水環境学会
  • 全国湖沼河川養殖研究会第76回大会(福井県)  [Not invited]
    中村太士
    2003
  • 「川の自然再生」セミナーテキスト(財団法人リバーフロント整備センター)  [Not invited]
    中村太士
    2003
  • 水循環シンポジウム−21世紀の研究課題と展望−(日本学術会議・メカニクス構造研究連絡委員会・水力学、水理学専門委員会・社会環境工学研究連絡委員会・水資源学専門委員会)  [Not invited]
    中村太士
    2003
  • 釧路湿原自然再生大会(釧路湿原自然再生大会実行委員会)  [Not invited]
    中村太士
    2003
  • 自然環境共生技術フォーラム講演録(自然環境共生技術フォーラム)  [Not invited]
    中村太士
    2003
  • 森林の公益的機能の限界と可能性(社団法人北海道造林協会)  [Not invited]
    中村太士
    2003
  • The nature restoration project in Kushiro Mire and Shibetsu River  [Not invited]
    Nakamura, F
    International symposium on renaturalization of a river basin by eco-compatible and adaptive management  2002/09  Tokyo
  • 釧路湿原及び標津川流域における再生事業  [Not invited]
    中村太士
    川の自然再生シンポジウム実行委員会  2002/09
  • Decline of ecological function of riparian zone in association with pasture development in Japan  [Not invited]
    Futoshi Nakamura
    The Organizing Committee of OASERD・ Obihiro University of Agriculture and Veterinary Medicine  2002/04  Obihiro,Japan
  • Effects of Dams and Channel Works on Riverine Habitat in Mountainous Streams in Northern Japan  [Not invited]
    Nakamura, F
    United Nations University International Symposium on Conservation of Mountain Ecosystems  2002/02  Tokyo
  • 社会全体で支える森林・流域管理  [Not invited]
    かながわ発「水源環境」シンポジウム−水源環境保全の施策と税制を考える全国シンポジウム−(コメンテーター)  2002  神奈川県
  • 自然再生事業と順応的管理:自然と共生する豊かな生活空間をめざしてX 平成14年度環境セミナー講演録  [Not invited]
    第3回環境セミナー  2002  北海道開発局:
  • 釧路湿原及び標津川流域における再生事業  [Not invited]
    国際シンポジウム 川の自然再生講演録 第3回世界水フォーラムに向けて  2002  「川の自然再生シンポジウム」実行委員会
  • 自然と共生する豊かな生活空間をめざしてX 平成14年度環境セミナー講演録(北海道開発局:第3回環境セミナー)  [Not invited]
    中村太士
    2002
  • 社会全体で支える森林・流域管理:かながわ発「水源環境」シンポジウム−水源環境保全の施策と税制を考える全国シンポジウム−(神奈川県)  [Not invited]
    中村太士
    2002
  • Ecological functions of riparian zone - Presentation of required buffer width in Japan -.  [Not invited]
    Nakamura, F
    The International Workshop on efficiency of purification processes in riparian zones. Their design and planning in agricultural watersheds.  2001/11  Kushiro
  • 北海道における自然復元の考え方と課題−釧路湿原の保全および標津川再蛇行化計画を事例として−  [Not invited]
    中村太士
    応用生態工学研究会  2001/09  東京
  • Fluvial Geomorphology and Environments (Session theme).  [Not invited]
    Futoshi Nakamura
    Fifth International Conference on Geomorphology  2001/09
  • 北海道渡島地方小渓流河川における実験的管理の試み−特徴ある魚類群集の保全−  [Not invited]
    佐川志朗, 中村太士, 妹尾優二, 木村明彦, 三沢勝也, 入江潔, 藤田真人, 渡辺敏也
    応用生態工学研究会  2001/09  東京
  • The effects of dams on the regeneration process of riparian tree species.  [Not invited]
    Nakamura, F
    Fifth International Conference on Geomorphology  2001/09
  • Interaction between fluvial geomorphology and woody debris in different geological setting in Japanese streams.  [Not invited]
    Mishima, Y, Nakamura, F
    Fifth International Conference on Geomorphology.  2001/09
  • パッカー法を用いた砂礫河床における透水係数の測定  [Not invited]
    山田浩之, 中村太士, 渡邊康玄, 村上まり恵, 野上毅
    応用生態工学研究会  2001/09  東京
  • Interactions between geomorphic and ecological processes and riverine habitat (Symposium theme).  [Not invited]
    Futoshi Nakamura
    Fifth International Conference on Geomorphology  2001/09
  • 真駒内川における魚類の生息環境に関する実験的管理の実践  [Not invited]
    加村邦茂, 渡辺恵三, 中村太士, 渡邊康玄, 野上毅, 土屋進, 岩瀬晴夫
    応用生態工学研究会  2001/09  東京
  • Measuring hydraulic permeability in a streambed using Packer test.  [Not invited]
    Yamada, H, Nakamura, F, Murakami, M. Nogami, T, Watanabe, Y
    Fifth International Conference on Geomorphology  2001/09
  • 河川環境および構造物の評価手法に関する景観生態学的研究  [Not invited]
    第4回水源地生態研究セミナー  2001  財団法人ダム水源地環境整備センター
  • 水源地生態研究会議の成果の活用−影響の予測・評価、保全対策への活用を考える−  [Not invited]
    第4回水源地生態研究セミナー(パネルディスカッション)  2001  財団法人ダム水源地環境整備センター
  • 川の自然再生 その目的と評価  [Not invited]
    国際シンポジウム川の自然再生 日本の、世界の、川が変わる(コーディネーター)  2001  国土交通省・財団法人日本生態系協会・財団法人北海道河川防災研究センター
  • 現地実験をベースにした順応的管理の構想と実践  [Not invited]
    第9回自然共生河川研究会  2001  財団法人リバーフロント整備センター・財団法人ダム水源地環境整備センター
  • 国際シンポジウム川の自然再生 日本の、世界の、川が変わる(国土交通省・財団法人日本生態系協会・財団法人北海道河川防災研究センター)  [Not invited]
    中村太士
    2001
  • 第4回水源地生態研究セミナー(財団法人ダム水源地環境整備センター)  [Not invited]
    中村太士
    2001
  • 第9回自然共生河川研究会(財団法人リバーフロント整備センター・財団法人ダム水源地環境整備センター)  [Not invited]
    中村太士
    2001
  • Dynamics of wood in rivers in the context of ecological disturbance  [Not invited]
    Nakamura, F
    First International conference on wood in world rivers  2000/10
  • 河畔林という生態環境  [Not invited]
    第38回日本水環境学会セミナー 「水辺の生態環境の保全と修復」  2000  社団法人日本水環境学会
  • 物質の流れと生物の生息場環境−釧路湿原を対象にして−  [Not invited]
    中村太士
    日本生態学会  1999/03
  • 流域一貫/森と川と人のつながりを求めて  [Not invited]
    平成11年度公開河川講座−川の未来とパートナーシップによる川づくりを考える−  1999  建設省徳島工事事務所:徳島県
  • 河川法改正/河川管理の新しい方向を考える  [Not invited]
    平成11年度公開河川講座−川の未来とパートナーシップによる川づくりを考える−(パネルディスカッション)  1999  建設省徳島工事事務所:徳島県
  • 平成11年度公開河川講座−川の未来とパートナーシップによる川づくりを考える−(建設省徳島工事事務所・徳島県)  [Not invited]
    中村太士
    1999
  • Application of landscape ecology to watershed management ? How we can restore ecological functions in fragmented landscape-  [Not invited]
    Nakamura, F
    The Korean Network for Landscape Ecology  1998/01
  • 水辺林の更新動態と生態学的機能−これまでの研究紹介と今後の展望  [Not invited]
    第1回水源地生態研究セミナー講演集  1998  財団法人ダム水源地環境整備センター
  • 第1回水源地生態研究セミナー講演集(財団法人ダム水源地環境整備センター)  [Not invited]
    中村太士
    1998
  • 流域における土地利用変遷と河川環境の変化  [Not invited]
    中村太士
    東京農工大学農学部  1997/11
  • 水辺林の生態的機能とその管理:生物機能関係資料集 ?12  [Not invited]
    平成9年度バイオコスモス計画テーマ別研究会 森と川と海と魚  1997  水産庁日本海区水産研究所・農林水産技術会議事務局・社団法人農林水産技術情報協会:
  • 河川の土砂動態と水辺域の生態的保全  [Not invited]
    第3回地形工学セミナー 地形学から工学への提言  1997  日本地形学連合
  • 平成9年度バイオコスモス計画テーマ別研究会 森と川と海と魚(水産庁日本海区水産研究所・農林水産技術会議事務局・社団法人農林水産技術情報協会)  [Not invited]
    中村太士
    1997
  • 水辺林の更新動態と河川生態系における役割  [Not invited]
    (社)砂防学会50周年記念シンポジウム  1997  (社)砂防学会50周年記念シンポジウム実行委員会
  • 域的視点からみた釧路湿原保護の現状と課題  [Not invited]
    中村太士
    野生生物保護学会  1996/10
  • 緑の砂防 −流域における土砂動態と河畔域の保全  [Not invited]
    1995年度(第31回)水工学に関する夏期研修会  1995  土木学会水理委員会
  • 森林科学の分野から  [Not invited]
    演習林フォーラム−21世紀を目指して−  1994  北海道大学農学部
  • 演習林フォーラム−21世紀を目指して−(北海道大学農学部長)  [Not invited]
    中村太士
    1994
  • 河川の生態環境の評価・保全に関わる研究の現状−生態系管理の視点から−:2006/6/22: 環境科学研究所生物研究連絡会((財)電力中央研究所)1997年11月19・20日:岐阜県:Session?「河川における自然環境の回復と保全」  [Not invited]
  • 流域の土地利用と河川環境のつながり−水辺域の構造と機能の回復をめざして−  [Not invited]
    世界河川会議論文集
  • Quantitative assessment of biodiversity loss in river/stream environment in Japan.  [Not invited]
    Asia Pacific Biodiversity Observation Network  (Tokyo, Japan).
  • Connectivity and dynamics of river and riparian landscape - Cascading effects of human impacts in Japan -.  [Not invited]
    River Corridor Restoration Conference 11.  (Ascona, Switzerland).
  • Shifting mosaic in maintaining river-floodplain ecosystem and its degradation in Japan.  [Not invited]
    International Workshop on Ecosystem-Science & -Engineering Approach toward Conservation of Biodiversity.  2010 (Nagoya, Japan).
  • Restoration of the fish and invertebrate habitat: The re-meandering project of a large river in northern Japan.  [Not invited]
    94th Ecological Society of America annual meeting,  (Albuquerque, New Mexico, USA)
  • Restoration strategies for rivers, floodplains and wetlands in Kushiro Mire and Shibetsu River, northern Japan.  [Not invited]
    International Symposium on the 4 Major Rivers Ecological Conservation and Restoration.  (International Convention Center (Millennium), Sang Myung University, Seoul, Korea)
  • Introduction of JICA training course regarding watershed ecosystem management.  [Not invited]
    International Workshop on the Planning on Field Training Course for the Integrated Environmental Sciences.  (Faculty of Environmental Earth Science, Hokkaido University, Japan)
  • Historical degradation of wetland and lake ecosystems associated with landuse development in Kushiro River catchment, northern Japan.  [Not invited]
    The 5th Japan-Korea-China International Workshop ? Present Earth Surface Processes and Historical Environmental Changes in East Asia.  (Hakodate, Japan)
  • Scale-dependent controls on the fluvial export of large wood  [Not invited]
    International Symposium of Innovative Forest Disasters R&D Center ? Current status and future issues in innovative forest disasters control  (Kangwon National University, College of Forest & Environmental Sciences, Korea)
  • Degradation and restoration of rivers and wetlands in Hokkaido, northern Japan  [Not invited]
    International Conference on Landscape and Ecological Engineering Issues and Problems for Environmental Restoration 2007.  KumRyong Academy House, Seoul National University, Korea
  • Rapid shrinkage of Kushiro Mire, the largest mire in Japan, due to increased sedimentation associated with land-use development in the catchment  [Not invited]
    GLP Symposium on "Impacts of Global Change on Vegetation and Cycling of Materials in Ecosystems"  Hokkaido University, Sapporo, Japan
  • River alteration and its ecological consequences from reach?to catchment scale  [Not invited]
    Gravel-Bed Rivers 6 ? From process understanding to river restoration.  St. Jakob, Austria
  • Current environmental problems and restoration efforts in the Kushiro Mire, the largest wetland in Japan.  [Not invited]
    .2005 World Wetlands Day Ceremony and Symposium.  Changnyeong-gun, Korea
  • Catchment management issues in Japan. "Sediment management in river systems: Basin scale approaches to predicting land to ocean responses"  [Not invited]
    International Workshop  Gisborne, Waipaoa River Basin, New Zealand
  • The nature restoration project in Kushiro Mire  [Not invited]
    International symposium on river restoration.  Tokyo, Japan
  • Effects of dams and channel works on riverine habitat in mountainous streams  [Not invited]
    UNU International Symposium on Conservation of Mountain Ecosystems.  Tokyo, Japan
  • Ecological Functions of Riparian Zone -Presentation of required buffer width in Japan-  [Not invited]
    Proceedings of the International Workshop on Efficiency of Purification Processes in Riparian Buffer Zones Their Design and Planning in Agricultural Watersheds:  Organizing Committee for International Workshop of Riparian Buffer zones, Kushiro, Japan
  • Dynamics of wood in rivers in the context of ecological disturbance  [Not invited]
    First International conference on wood in world rivers.  Oregon, USA
  • Application of landscape ecology to watershed management ? How we can restore ecological functions in fragmented landscape-  [Not invited]
    Landscape Ecology: Principle, Concept and Application  The Korean Network for Landscape Ecology, Seoul, Korea
  • Decline of ecological function of riparian zone in association with pasture development in Japan: International symposium on global perspective in forest conservation and sustainable agriculture.  [Not invited]
    The Organizing Committee of OASERD・  Obihiro University of Agriculture and Veterinary Medicine, 2002 Obihiro, Japan

Works

  • 大学との連携による森林づくり・地域づくりシンポジウム
    2008
  • 第11回水源地生態研究セミナー
    2008
  • 北海道洞爺湖サミット記念「国際交流森林環境フォーラム」
    2008
  • 自然再生に向けた県民参加と協働のあり方を考える
    2008
  • NPO法人 北海道魚道研究会
    2007
  • 平成19年度 北海道大学公開講座「くらしを創る-安全と安心の科学」
    2007
  • 損保ジャパン札幌コールセンター開設記念「市民のための環境公開講座」(パネリスト)損保ジャパン
    2007
  • 矢作川「川会議」
    2007
  • 北海道民有林治山事業60周年記念講演会((社)北海道治山林道協会)
    2007
  • 「河川工作物が生物生息環境に与える影響と課題」(講演)((財)北海道河川防災研究センター)
    2007
  • (社)日本環境アセスメント協会第2回セミナー
    2007
  • パイロットフォレスト造成50周年記念シンポジウム(北海道森林管理局)
    2006
  • 環境科学研究所生物研究連絡会((財)電力中央研究所)
    2006
  • 河川生態系連続講演会「流域生態系を育む河川ネットワーク」特定非営利活動法人 日本国際湿地保全連合
    2006
  • 河川環境目標検討委員会(国土交通省)
    2005
  • 河川生態系連続講演会 流域生態系を育む河川ネットワーク(特定非営利活動法人日本国際湿地保全連合)
    2005
  • 阿蘇くじゅう国立公園指定70周年記念-阿蘇草原再生シンポジウム(環境省)
    2005
  • 「ふれあい自然ワークショップ」環境講演会(浜中町教育委員会)
    2004
  • 第491回建設技術講習会テキスト(環境問題):(社団法人全日本建設技術協会)
    2004
  • 第1回シンポジウム 自然と共生する社会づくり -自然再生事業の実践的課題と展望-((社)自然環境共生技術協会)
    2004
  • 第7回水源地生態研究セミナー(ダム水源地環境整備センター)
    2004
  • 第2回「川の自然再生」セミナー(財団法人リバーフロント整備センター)
    2004
  • 全国湖沼河川養殖研究会第76回大会(福井県)
    2003
  • 「川の自然再生」セミナーテキスト(財団法人リバーフロント整備センター)
    2003
  • 水循環シンポジウム-21世紀の研究課題と展望-(日本学術会議・メカニクス構造研究連絡委員会・水力学、水理学専門委員会・社会環境工学研究連絡委員会・水資源学専門委員会)
    2003
  • 釧路湿原自然再生大会(釧路湿原自然再生大会実行委員会)
    2003
  • 自然環境共生技術フォーラム講演録(自然環境共生技術フォーラム)
    2003
  • 釧路湿原自然再生大会(釧路湿原自然再生大会実行委員会)
    2003
  • 森林の公益的機能の限界と可能性(社団法人北海道造林協会)
    2003
  • 自然と共生する豊かな生活空間をめざしてX 平成14年度環境セミナー講演録(北海道開発局:第3回環境セミナー)
    2002
  • 社会全体で支える森林・流域管理:かながわ発「水源環境」シンポジウム-水源環境保全の施策と税制を考える全国シンポジウム-(神奈川県)
    2002
  • 国際シンポジウム川の自然再生 日本の、世界の、川が変わる(国土交通省・財団法人日本生態系協会・財団法人北海道河川防災研究センター)
    2001
  • 第4回水源地生態研究セミナー(財団法人ダム水源地環境整備センター)
    2001
  • 第4回水源地生態研究セミナー(財団法人ダム水源地環境整備センター)
    2001
  • 第9回自然共生河川研究会(財団法人リバーフロント整備センター・財団法人ダム水源地環境整備センター)
    2001
  • 平成11年度公開河川講座-川の未来とパートナーシップによる川づくりを考える-(建設省徳島工事事務所・徳島県)
    1999
  • 平成11年度公開河川講座-川の未来とパートナーシップによる川づくりを考える-(建設省徳島工事事務所・徳島県)
    1999
  • 第1回水源地生態研究セミナー講演集(財団法人ダム水源地環境整備センター)
    1998
  • 平成9年度バイオコスモス計画テーマ別研究会 森と川と海と魚(水産庁日本海区水産研究所・農林水産技術会議事務局・社団法人農林水産技術情報協会)
    1997
  • 演習林フォーラム-21世紀を目指して-(北海道大学農学部長)
    1994

MISC

  • 北沢宗大, 山浦悠一, 先崎理之, 埴岡雅史, 大橋春香, 小黒芳生, 松井哲哉, 中村太士  日本生態学会大会講演要旨(Web)  68th-  2021
  • 西尾太希, 石山信雄, 根岸淳二郎, 森本淳子, 中村太士  日本生態学会大会講演要旨(Web)  67th-  2020
  • 三浦一輝, 石山信雄, 石山信雄, 川尻啓太, 渥美圭佑, 長坂有, 折戸聖, 町田善康, 臼井平, GAO Yiyang, 能瀬晴菜, 根岸淳二郎, 中村太士  保全生態学研究  24-  (1)  2019
  • 中川智裕, 根岸淳二郎, 中村太士  応用生態工学会研究発表会講演集  23rd-  2019
  • 堀田亘, 森本淳子, 井上貴央, 鈴木智之, 梅林利弘, 尾張敏章, 柴田英昭, 石橋聰, 原登志彦, 中村太士  日本森林学会大会学術講演集  130th-  2019
  • Yuki Yabuhara, Yuichi Yamaura, Takumi Akasaka, Satoshi Yamanaka, Futoshi Nakamura  Forest Ecology and Management  454-  2019/01/01  [Not refereed][Not invited]
     
    © 2019 Elsevier B.V. In fragmented temperate landscapes, species responses to patch and landscape structures are likely to vary across seasons. However, few studies have examined the dynamic effects on biodiversity across seasons. We examined the effects of patch attributes and connectivity and seasonal variation in the effects of these environmental variables on forest bird communities at woodland fragments surrounded by agricultural land across three seasons (breeding, dispersal, and wintering seasons). We surveyed birds in woodland remnants and examined the effects of patch area, woodland connectivity, woodland type, and three interaction terms between these environmental variables and season (patch area × season, connectivity × season, and woodland type × season) on forest bird communities. In the results, species richness, abundance and composition of forest bird communities were associated with patch attributes and connectivity, and some of these associations varied depending on the season. Specifically, there were significantly higher abundances of specialist birds in riparian woodlands compared to conifer woodlands during the breeding season, whereas this pattern was reversed during the winter. In addition, we found the negative effects of patch area during the dispersal and wintering seasons and the positive effect of connectivity during the dispersal season on generalist bird abundances. These results suggest that woodland patches with high conservation values differ among three seasons. The conservation planning for a fragmented landscape therefore needs to consider the role of patch attributes and connectivity during multiple seasons rather than just the breeding season.
  • Nobuo Ishiyama, Masahiro Ryo, Taiga Kataoka, Shigeya Nagayama, Masanao Sueyoshi, Akira Terui, Terutaka Mori, Takumi Akasaka, Futoshi Nakamura  Conservation Biology  32-  (6)  1403  -1413  2018/12/01  [Not refereed][Not invited]
     
    © 2018 Society for Conservation Biology Large dams provide vital protection and services to humans. However, an increasing number of large dams worldwide are old and not operating properly. The removal of large dams has excellent potential to restore habitat connectivity and flow regimes; therefore, projecting the related ecological consequences is an emerging need for water resource and ecosystem management. However, no modeling methods are currently available for such projections at the basin scale. We devised a scheme that integrates changes in flow regimes and habitat network structure into a basin-scale impact assessment of removal of large dams and applied it to the Nagara-Ibi Basin, Japan. We used a graph-theoretical approach and a hydrological model, to quantify changes in habitat availability for 11 freshwater fishes at the basin scale under multiple removal scenarios. We compared these results with the change predicted using a conventional scheme that considered only changes to the habitat network due to dam removal. Our proposed scheme revealed that an increase in flow variability associated with dam removal projected both positive and negative effects on basin-scale habitat availability, depending on the focal species, endangered species had a negative response to dam removal. In contrast, the conventional approach projected only positive effects for all species. This difference in the outcomes indicates that large-dam removal can have negative and positive effects on watershed restoration due to changes in flow regimes. Our results also suggest the effect of removal of large dams may depend on the dams and their locations. Our study is the first step in projecting ecological trade-offs associated with the removal of large dams on riverscapes at the basin scale and provides a foundation for future process-based watershed restoration.
  • A new record of distributions of Margaritifera togakushiensis in Esashi Town, Hokkaido, northern Japan
    Kazuki Miura, Keita Kawajiri, Taira Usui, Nobuo Ishiyama, Yoshihiro B. Akiyama, Keisuke Atsumi, Junjiro N. Negishi, Futoshi, Nakamura  Bulletin of the Okhotsk Museum Esashi  9-  23  -29  2018/03  [Not refereed][Not invited]
  • 島谷 幸宏, 西廣 淳, 広田 純一, 宮内 泰介, 天野 邦彦, 中村 太士  応用生態工学 = Ecology and civil engineering  20-  (1)  147  -159  2017/09  [Not refereed][Not invited]
  • 吉井 千晶, 山浦 悠一, 小林 慶子, 竹中 健, 赤坂 卓美, 中村 太士  保全生態学研究 = Japanese journal of conservation ecology  22-  (1)  105  -120  2017/05  [Not refereed][Not invited]
  • Terui, A., Akasaka, T., Negishi, J.N., Uemura, F., Nakamura, F.  Ecological Research  32-  (1)  27  -35  2016  [Not refereed][Not invited]
     
    A variety of organisms mediate river-terrestrial linkages through spatial subsidies. However, most empirical studies have classified organisms rather broadly (e.g., by functional group or taxonomic family) and have dismissed species-level linkages at the interface of ecosystems. Here, we show how allochthonous resource use varies among taxonomically similar species of ground beetles (family Carabidae) across seasons (June-September). We investigated seasonal shifts in the distribution of five beetle species and their dietary responses to spatial subsidies (emerging aquatic insects) in a Japanese braided river. Despite their taxonomic closeness, the ground beetles showed species-specific responses to spatial subsidies, and beetle distribution patterns tended to coincide with their diets. Overall, 1-56% of ground beetle diets were derived from aquatic prey. One genus (Bembidion spp.) mainly consumed aquatic prey, while three species fed primarily on terrestrial prey across all seasons. However, one species (Lithochlaenius noguchii) showed shifts in its diet from aquatic to terrestrial prey according to subsidy availability. The observed variation in allochthonous resource use was likely related to species-specific foraging modes, physiological tolerance to dry conditions, and interspecific competition. Our findings suggest that considering species-specific interactions is necessary to fully understand cross-system interactions and recipient food-web dynamics.
  • Nobuo Ishiyama, Shigeya Nagayama, Haruo Iwase, Takumi Akasaka, Futoshi Nakamura  Ecology and Civil Engineering  119-  (2)  143  -164  2016/01/01  [Not refereed][Not invited]
     
    Japan is known as a nation with high dam density. The mid- and downstream sections of most Japanese rivers are fringed by lateral embankments, causing serious deterioration of aquatic connectivity in the upstream-downstream, the longitudinal direction and the channel-floodplain, the lateral direction. The present review summarizes general causes of the fragmentation, restoration methods for riverine connectivity, and current status and future challenges of the restoration in inter-levee and outside-levee floodplains of Japanese rivers. In the inter-levee floodplain, we detected four restoration types pertaining to longitudinal fragmentation by physical and invisible barriers associated with water temperature and quality, and six restoration types concerning lateral connectivity. In marked contrast to the inter-levee floodplains, outside-levee floodplains have already been severed from a dynamic flooding process. In such altered systems, the management of an artificial habitat network such as a paddy-field or a pond is a major mechanism for creating alternative dispersal pathways. We also found that many of above restoration techniques present practical issues that limit the restoration effects on specific species or life stages and risk further degradation due to inappropriate selection of sites or procedures. Human pressure on freshwaters and the resilience of the ecosystems have been changing gradually, suggesting that Japanese river managers need to select appropriate techniques depending on these changes to restore the connectivity more efficiently. Realistically, "Habitat Creation" and "Partial restoration" focusing on the artificial or semi-natural connectivity are major strategies in the short run. On the other hand, "Full restoration" should be the major goal in a time span of a few decades, in the context of future social changes such as population decline and deterioration of infrastructures. In addition, a database of the location of low-head dams is needed to prioritize the restoration of the sites for connectivity both in the inter- and outside-levee floodplains.
  • 中村 太士  河川  71-  (10)  13  -17  2015/10
  • 中村 太士  旭硝子財団助成研究成果報告 Reports of research assisted by the Asahi Glass Foundation  1  -4  2015
  • Nakamura, F., Seo, J.I., Akasaka, T., Swanson, F.J.  Geomorphology  279-  176  -187  2015  [Not refereed][Not invited]
     
    Water, sediment, and large wood (LW) are the three key components of dynamic river-floodplain ecosystems. We examined variations in sediment and LW discharge with respect to precipitation, the presence of dams, land and river use change, and related channel incision and forest expansion on gravel bars and floodplains across Japan. The results indicated that unit sediment discharge and unit LW discharge were smaller in southern Japan where precipitation intensity is generally much greater. Effective precipitation, an index that takes current and antecedent precipitation into account, was a strong predictor of discharge in small watersheds, but not in larger watersheds. However, precipitation intensities related to unit sediment discharge in intermediate and large watersheds were smaller than those associated with unit LW discharge, which we attribute to differences in particle shape and size and also transport mechanisms. The relationship between river flow and discharge of sediment and LW lead us to posit that discharges of these components are supply limited in southern Japan and transport limited in northern Japan. The cross-sectional mean low-flow bed elevation of gravel-bed and sand-bed rivers in Japan decreased by similar to 0.71 and 0.74 m on average, respectively, over the period 1960-2000. Forest expansion on bars and floodplains has been prominent since the 1990s, and trees apparently began to colonize gravel bars similar to 10 to 20 years after riverbed degradation began. Forest recovery in headwater basins, dam construction, gravel mining, and channelization over the past half century are likely the dominant factors that significantly reduced downstream sediment delivery, thereby promoting channel incision and forest expansion. Changes in rivers and floodplains associated with channel incision and forest expansion alter the assemblages of aquatic and terrestrial organisms in riverine landscapes of Japan, and climate change may contribute to this change by intensified precipitation. Additionally, regime shifts of water, sediment, and LW may continue or they may reach a dynamic state of quasi-equilibrium in the future. Continued monitoring of these three components, taking into account their geographic variation, is critical for anticipating and managing future changes in river-floodplain systems in Japan and around the world. (C) 2016 Elsevier B.V. All rights reserved.
  • Yabe Atsuko, Akasaka Takumi, Yabuhara Yuki, Nakamura Futoshi  The Japanese Forest Society Congress  126-  (0)  2015  [Not refereed][Not invited]
     
    [in Japanese]
  • Hideyuki Kawai, Shigeya Nagayama, Hirokazu Urabe, Takumi Akasaka, Futoshi Nakamura  ENVIRONMENTAL BIOLOGY OF FISHES  97-  (5)  575  -586  2014/05  [Not refereed][Not invited]
     
    Recent studies have demonstrated that the energetic profitability (net energy intake potential; NEI potential) of a habitat, which is calculated as the gross energy gain from foraging minus the energy expenditure from swimming at a focal point, may be a useful tool for predicting the salmonid biomass. The effectiveness of the NEI potential should be tested in various systems. Even if the NEI potential is validated, its predictive accuracy and transferability could be limited if the cover habitat, which is known to be an important factor for determining salmonid abundance, is not considered. We tested whether the NEI potential is effective for predicting the salmonid biomass even in a stream with abundant cover and whether combining the NEI potential and cover effects can improve the predictability of fish biomass using a generalized linear model. Our results demonstrated that the NEI potential could generally predict the fish biomass (percent deviance explained = 79.9 %), and the model that incorporated both the NEI potential and the cover ratio improved the predictive accuracy (percent deviance explained = 88.5 %). These results suggest that energetic profitability can be an effective indicator for assessing habitat quality and is relatively transferable to other systems. Furthermore, when cover effects are considered, the habitat quality is more accurately represented; thus, combining the energetic profitability and the cover effects might improve the transferability of the assessment across habitats.
  • Aimi Fuyuki, Yuichi Yamaura, Yuri Nakajima, Nobuo Ishiyama, Takumi Akasaka, Futoshi Nakamura  Urban Forestry and Urban Greening  13-  (2)  397  -402  2014/01/01  [Not refereed][Not invited]
     
    We examined factors that affect egg distributions of amphibians, which are currently declining globally, in urban areas. We counted the number of egg masses of two amphibian species (Hynobius retardatus and Rana pirica) in ponds in urban green spaces during two years (2011 and 2012) and investigated the effects of local and landscape factors on them. Forest area in green spaces and pond area had positive effects, and distance from continuous forests in the suburbs and the rate of pond shore protection had negative effects on the number of eggs. Among these factors, distance from continuous forests and pond area had strong effects on egg distributions. These results suggest the importance of water habitat size and the need for colonization by amphibians from surrounding continuous forests. To conserve urban amphibian assemblages, the preservation of ponds with sufficient area and continuous forests close to urban habitats would be important. © 2013 Elsevier GmbH.
  • Nobuo Ishiyama, Takumi Akasaka, Futoshi Nakamura  Aquatic Sciences  76-  (3)  437  -449  2014/01/01  [Not refereed][Not invited]
     
    Management of wetland connectivity is important for biodiversity conservation. In the modern agricultural landscape, the natural connections between floodplain wetlands have been greatly altered. Agricultural ditches and channelized streams are widely distributed in floodplains, which may contribute to the maintenance of wetland connectivity and biodiversity. To determine how these watercourse networks affect wetland biodiversity, we examined the relationship between the species richness of aquatic animals and wetland connectivity, with a special focus on species mobility. From July to August 2011, fish and aquatic insects were collected from 24 wetlands in northern Japan. To determine the degree of wetland connectivity, we assessed the relative importance of individual wetlands in maintaining the entire wetland network using two connectivity indices: hydrologic connectivity via watercourses and spatial connectivity defined as Euclidian distances between wetlands using graph theory. We found that only high mobility groups of both taxa could enhance species richness in either a hydrologic (fish) or spatial (insect) wetland network. The species richness of insects with high-flying ability was found to increase as spatial connectivity increased. Furthermore, the species richness of fish with high-swimming ability was positively influenced by hydrologic connectivity, most likely because highly mobile species were able to reach suitable habitats and migrate from source populations in a wetland network owing to their good mobility. Our findings indicate that hydrologic network is important for maintaining biodiversity as well as spatial connectivity. It is important to focus conservation efforts on key wetlands with high hydrologic and spatial connectivity in future wetland management. © 2014 Springer Basel.
  • 柴田昌俊, 森本淳子, 三島啓雄, 比嘉基紀, 志田祐一郎, 中村太士  日本生態学会大会講演要旨集  60th-  165  2013/03/05  [Not refereed][Not invited]
  • 中島夕里, 山浦悠一, 赤坂卓美, 愛甲哲也, 三島啓雄, 森本淳子, 中村太士  日本生態学会大会講演要旨集  60th-  168  2013/03/05  [Not refereed][Not invited]
  • NAKAMURA Futoshi  Boreal forest research  (61)  1  -2  2013/02/18
  • MORIMOTO Miho, MORIYA Yoshiaki, MORIMOTO Junko, NAKAMURA Futoshi  日本森林学会北海道支部論文集  (59)  17  -20  2011/02/19
  • Naito Sayoko, Yoshida Toshiya, Nakamura Futoshi  The Japanese Forest Society Congress  122-  (0)  560  -560  2011  [Not refereed][Not invited]
  • Kamoka Rui, Yamaura Yuichi, Yabuhara Yuki, Akasaka Takumi, Akashi Nobuhiro, Uno Hiroyuki, Nakamura Futoshi  The Japanese Forest Society Congress  123-  (0)  Pb169  -Pb169  2011  [Not refereed][Not invited]
  • 森本淳子, 三島啓雄, 間野勉, 中村太士  日本生態学会大会講演要旨集  57th-  207  2010/03  [Not refereed][Not invited]
  • Miya Hisashi, Yoshida Toshiya, Noguchi Mahoko, Yasuda Akira, Nakamura Futoshi  The Japanese Forest Society Congress  121-  (0)  413  -413  2010  [Not refereed][Not invited]
  • 宮久史, 吉田俊也, 野口麻穂子, 米康充, 小熊宏之, 坂井励, 高橋廣行, 小宮圭示, 小野貴司, 中村太士  日本生態学会大会講演要旨集  56th-  312  2009/03/17  [Not refereed][Not invited]
  • Miya Hisashi, Yoshida Toshiya, Noguchi Mahoko, Yasuda Akira, Nakamura Futoshi  The Japanese Forest Society Congress  120-  (0)  508  -508  2009  [Not refereed][Not invited]
  • Morimoto Junko, Takei Naoko, Sato Hirokazu, Kaneko Masami, Nakamura Futoshi  Landscape ecology and management  13-  (1)  2,113-121  -121  2009  [Not refereed][Not invited]
     
    Controls of floods and water quality are of great concern in Shiraoi town, Hokkaido. The function of soil and water conservation in three sub-watersheds in the town was evaluated and its reliability was tested. The methods to evaluate forest function, which was developed by Hokkaido prefecture government, are easy to employ, and the results are easy to understand for local people, and therefore we used them. The chronological changes in those functions were compared among three sub-watersheds in the following three years. They are 1948 representing the period of postwar rehabilitation, 1976 being post rapid growth period in Japanese economy, and 2006, the period after the collapse of bubble economy. Agreements of the scores and vegetation changes due to the change of social situation were examined. In results, 1) function of soil and water conservation were degraded temporarily after clear-cutting, 2) conversion of land use to the quarries caused a decline in the function of soil and water conservation, which may continue for a long time, 3) function of mitigating drought and flood was most sensitively affected by forest exploitation, 4) function of controlling water quality greatly declined when riparian zone having steep slopes was broadly developed. The scores were mostly explained by vegetation changes due to the change of social situation. While comparing scores of other sub-watersheds pointed out problems to be solved. It is necessary to simplify the evaluation procedure and show standards of judgment with regard to scores to make the guideline more lucid one.
  • Jung Il Seo, Futoshi Nakamura, Daisuke Nakano, Hidetaka Ichiyanagi, Kun Woo Chun  WATER RESOURCES RESEARCH  44-  (10)  2008/10  [Not refereed][Not invited]
  • AHN Young Sang, NAKAMURA Futoshi, KIZUKA Toshikazu, NAKAMURA Yugo  地形  29-  (1)  71  -71  2008
  • Futoshi Nakamura  Ecology of Riparian Forests in Japan: Disturbance, Life History, and Regeneration  2008
  • Futoshi Nakamura, Yôichi Kawaguchi, Daisuke Nakano, Hiroyuki Yamada  Developments in Earth Surface Processes  11-  501  -523  2007  
    We describe the relationship between disturbance regimes, the life history traits of aquatic and riparian organisms, and effects of human activity, using Japanese gravel-bed rivers in the Asia Monsoon Belt as an example. The consideration of various roles of disturbance in creating a spatial and temporal pattern of habitats is made hierarchically at three spatial scales. Segment scale is the largest, represented by a braided river landscape on an alluvial fan. Riparian tree species direct their life history strategies to survive in the shifting habitat dynamics. Reservoirs constructed at the fan apex regulate flood disturbances and seasonal flow variation, changing the dynamic state to a monotonous, static habitat structure. Intermediate reach-scale structures are represented by pool-riffle sequences, gravel bars, secondary and abandoned channels and oxbow lakes. We focused particularly on the lateral variation of the entire valley floor and its stream channel, which provide critical habitats for spawning, hatching, rearing, wintering, feeding and dwelling as well as flow refugia for fish and macroinvertebrates. Bed instability resulting from an increased tractive force due to channel straightening and its impact on macroinvertebrate communities is also discussed. Finally, the smallest scale is the microhabitat seen as the interstitial spaces in gravel beds used by salmonid and benthic fish for all or some of their life stages. Sediment control dams and gravel mining in rivers and floodplains is causing gravel-size sediment starvation, whereas the introduction of fine sediment is substantially increased following land-use development. © 2008 Elsevier B.V. All rights reserved.
  • Miya Hisashi, Noguchi Mahoko, Yoshida Toshiya, Nakamura Futoshi  The Japanese Forest Society Congress  118-  (0)  569  -569  2007  [Not refereed][Not invited]
  • AHN Young Sang, NAKAMURA Futoshi, MIZUGAKI Shigeru, SATOH Hiroki  日本森林学会北海道支部論文集  (54)  136  -139  2006/02/24
  • Nakamura Futoshi  地形  27-  (1)  i  2006
  • Futoshi Nakamura, Daisuke Nakano, Yoichi Kawaguchi, Satomi Inahara  Chikei/Transactions, Japanese Geomorphological Union  27-  (1)  41  -64  2006/01  
    River ecosystem is spatiotemporally dynamic under frequent and intensive geomorphic disturbances, characterized by its fluctuating habitat availability. The species inhabiting there adapt themselves to the shifting habitat by developing various life-history strategies. In regulated rivers, however, suppressed disturbance and habitat dynamics threaten the disturbance-dependent communities. The recognition of important geomorphic perspectives is still in its infancy in conservation of river ecosystems in Japan. Riparian tree species have developed life-history strategies to increase the likelihood of arriving regeneration sites, where disturbance regimes are closely linked to the spatial and temporal availability of regeneration sites. River damming and channel modification severely diminish the critical function of geomorphic disturbance sustaining habitat diversity and abundance. Channel migration ceases in flow-regulated rivers, which may temporarily promote expansion of pioneer forest in the active channels. However, new geomorphic surfaces suitable for establishment of seedlings are no longer created because of altered peak flows and sediment supply, thereby threatening the recruitment opportunity and ultimate survival of their populations. Suppression of geomorphic disturbance also leads to the degradation of in-stream fauna. Channel straightening particularly simplifies geomorphic features of a river reach and diminishes longitudinal and lateral habitat diversity in its active channel. Flood control reduces inundation habitat and disrupts hydrologic connectivity between floodplain habitats (e.g., backwater and oxbow lakes), impacting fish and benthic invertebrates that require those habitats in their various life stages. A channel re-meandering experiment in the Shibetsu River, Hokkaido, demonstrates that the recovery of geomorphic dynamics can play significant roles in restoration of river ecosystems. Meandering reaches develop shallow edge habitat with low hydraulic stress along the inside of a convex, providing stable substrate for macroinvertebrate communities. Fallen trees provided by lateral erosion also promote macroinvertebrate colonization and become in-stream covers for fish communities. Geoecology in Japan as well as Europe and U.S. has long focused on vegetation pattern in alpine regions and has unexplored terrestrial and aquatic ecosystems in the vicinity of human activities. Knowledge in habitat dynamics and geomorphic processes is vital to ecosystem conservation and restoration. We believe that participation of geomorphologists is essential in future development of conservation and restoration strategies.
  • 宮 久史, 吉田 俊也, 中村 太士, 小鹿 勝利  日本森林学会大会発表データベース  116-  (0)  149  -149  2005  [Not refereed][Not invited]
  • Planning a forest road in consideration for minimizing impacts on stream
    Mita, T, Owari, T, Tachiki, Y, Ishizaki, H, Nakamura, F  Proceedings of the international seminar on new roles of plantation forestry requiring appropriate tending and harvesting operations (IUFRO International seminar 2002 Japan)  294  -300  2003  [Not refereed][Not invited]
  • 柴田 英昭, 中村 太士  水文・水資源学会誌  15-  (5)  2002/09/05  [Not refereed][Not invited]
  • 島谷 幸宏, 北村 眞一, 中村 太士  Front  14-  (6)  60  -63  2002/03  [Not refereed][Not invited]
  • 島谷 幸宏, 北村 眞一, 中村 太士  Front  14-  (5)  60  -63  2002/02  [Not refereed][Not invited]
  • SUGAWARA Osamu, NAKAMURA Futoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (48)  130  -132  2000/02/22
  • KAMURA KUNISHIGE, NAKAMURA FUTOSHI  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (48)  133  -135  2000/02/22
  • 中村太士  渓流岸態砂防学  1999
  • 中村 太士  砂防学会誌 : 新砂防 = Journal of the Japan Society of Erosion Control Engineering  50-  (6)  83  -83  1998/03/15
  • OOISHI Tomoko, SEINO Minoru, KIKUCHI Shun-ichi, YAJIMA Takashi, SHIMIZU Osamu, NAKAMURA Futoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (46)  64  -67  1998/02/10
  • 中村 太士  砂防学会誌 : 新砂防 = Journal of the Japan Society of Erosion Control Engineering  49-  (3)  68  -68  1996/09/15
  • 河畔林・渓畔林研究の現状と課題
    崎尾均, 中村太士, 大島康行  日本生態学会誌  45-  (3)  307  -310  1995/12  [Not refereed][Not invited]
  • 第41回生態学会大会自由式シンポジウム記録「渓畔域の生態的構造と機能-森林と河川の相互作用-」
    伊藤 哲, 鈴木和次郎, 金子有子, 崎尾 均, 中村太士  森林科学  (13)  60  -67  1995/10  [Not refereed][Not invited]
  • ONO Yugo, NAKAMURA Futoshi, ITO Akiko, SUGIMOTO Sachio  地形 = Transactions, Japanese Geomorphological Union  16-  (3)  271  -279  1995/07/25
  • NAKAMURA Futoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (42)  215  -217  1994/02/28
  • SAKAMOTO Tomoki, TUCHIYA Toshiyuki, SANO Makoto, NAKAMURA Futoshi, KAJI Koichi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (42)  211  -214  1994/02/28
  • ITO Akiko, NAKAMURA Futoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (42)  208  -210  1994/02/28
  • Kikuchi Shun-ichi, Yajima Takashi, Nakamura Futoshi  Research bulletins of the College Experiment Forests, Hokkaido University  51-  (1)  44  -73  1994/02
  • KIKUCHI Shun-ichi, SAWAI Osamu, SEINO Minoru, YAJIMA Takashi, SHIMIZU Osamu, NAKAMURA Fotoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (41)  232  -234  1993/02/28
  • SAWAI Osamu, SEINO Minoru, KIKUCHI Shun-ichi, YAJIMA Takashi, SHIMIZU Osamu, NAKAMURA Futoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (41)  235  -237  1993/02/28
  • NAKAMURA Futoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (41)  130  -132  1993/02/28
  • 中村 太士  北方林業  44-  (7)  p185  -190  1992/07
  • MIYABUCHI Yasuo, NAKAMURA Futoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (38)  249  -251  1990/03/01
  • MAKINO Akihisa, NISHIYAMA Yasuhiro, NAKAMURA Futoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (38)  252  -254  1990/03/01
  • MIYAZAKI Tomoyoshi, NAN-RI Tomoyuki, NAKAMURA Futoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (38)  242  -245  1990/03/01
  • DOKAI Takuji, NAKAMURA Futoshi, TANAKA Yumiko  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (37)  171  -173  1989/03/01
  • TAKEUCHI Masanobu, NAKAMURA Futoshi  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (37)  165  -167  1989/03/01
  • KIKUCHI Shun-ichi, NAKAMURA Futoshi, ARAYA Tohru  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (37)  162  -164  1989/03/01
  • NAKAMURA Futoshi, SHIMIZU Osamu, HIGASHI Saburo  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (34)  193  -195  1986/03/10
  • EGUCHI Toshihiro, NAKAMURA Futoshi, SHIMIZU Osamu  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (34)  202  -204  1986/03/10
  • SHIMIZU Osamu, NAKAMURA Futoshi, CHON Kun-Woo  Transactions of the Meeting in Hokkaido Branch of the Japanese Forestry Society  (34)  196  -198  1986/03/10
  • 中村 太士  日本林學會北海道支部講演集  (33)  215  -217  1985/03/20
  • 上條 哲也, 中村 太士, 新谷 融  日本林學會北海道支部講演集  (33)  206  -208  1985/03/20
  • 清水 収, 中村 太士, 新谷 融  日本林學會北海道支部講演集  (32)  271  -273  1984/03/20
  • 中村 太士, 新谷 融  日本林學會北海道支部講演集  (32)  265  -267  1984/03/20
  • 中村 太士, 新谷 融  日本林學會北海道支部講演集  (31)  255  -257  1983/03/20
  • 清水 収, 中村 太士, 東 三郎  日本林學會北海道支部講演集  (31)  249  -251  1983/03/20
  • 中村 太士, 馬場 仁志, 東 三郎  日本林學會北海道支部講演集  (30)  268  -270  1982/03/20
  • 馬場 仁志, 清水 宏, 中村 太士  日本林學會北海道支部講演集  (30)  271  -273  1982/03/20

Awards & Honors

  • 2018/04 内閣府 紫綬褒章
     
    受賞者: 中村 太士
  • 2018/02 北海道 北海道科学技術賞
     
    受賞者: 中村 太士
  • 2017/04 読売新聞社 読売農学賞
     
    受賞者: 中村 太士
  • 2017/04 日本農学会 日本農学賞
     
    受賞者: 中村 太士
  • 2013/03 北海道大学 研究総長賞
     
    受賞者: 中村 太士
  • 2012/04 内閣府 平成24年(第6回)みどりの学術賞
     
    受賞者: 中村 太士
  • 2011/03 財団法人 尾瀬保護財団 第14回 尾瀬賞
     釧路湿原における流域土地利用の累積的影響評価と生態学的保全及び復元に関する研究 
    受賞者: 中村 太士
  • 2009/07 日本生態学会 第15回生態学琵琶湖賞
     
    受賞者: 中村 太士
  • 2005/03 2005年度 日本森林学会賞

Research Grants & Projects

  • River restoration aiming at an increase of wild salmon resources
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2021/04 -2024/03 
    Author : 中村 太士, 渡邊 康玄, 卜部 浩一, 森田 健太郎
  • Responses of stream and riparian ecosystems to the regime shifts of flow, sediment, and forest, according to changes in resource management and climate change
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2018/04 -2021/03 
    Author : 中村 太士, 萱場 祐一, 山浦 悠一, 根岸 淳二郎
     
    河道内の樹林化は1990年代頃から急速に進展したと考えられており、その範囲は全国に及んでいる。樹林化は河道内の高い比高域(概ね堤内地盤高程度)で進む場合とそれより低い比高域で進む場合がある。高比高域における樹林化は、竹林の分布域拡大に見られるように人的圧力によるものと考えられたが、低比高域における樹林化はみお筋部の低下、土砂供給量の減少等自然攪乱の頻度・強度の減少に起因すると考えられた。 ダムに流出する流木量を2000年以前、2000~2009年、2010年以降について、ダム事務所に問い合わせデータを収集した。 札内川中流域縦断距離15km区間を対象に、2016年の洪水に伴う河川地形および樹林被覆状態の変化、それに伴う河川および河畔の生物の個体数や群集構造を定量化した。洪水により樹林被覆は約20%減少したが、河川内の底生動物や砂礫堆地表性甲虫の個体数や群集構造は洪水前から大きな変化を示さなかった。一方、飛翔性ハチ目については、砂礫堆を好む種群の個体数は相対的に減少し、これは、洪水による物理的な生息場のかく乱が、生息適地の拡大の影響を上回ったためと考えられた。 森林の連結性は概して森林への依存性が高い鳥類の多様性に正の影響を及ぼしていたが、森林への依存性が高くない種の多様性には、時に森林の面積が負に影響していた。これは、こうした種が森林以外の土地利用を利用できるためだと考えられた。また、針葉樹人工林は広葉樹天然林や河畔林と比較すると、繁殖期は低質な生息地として機能していたが、越冬期は逆に個体数が高く、季節を通すと一定の役割を担っていると考えられた。 気候変動による影響については、まずは水温への影響を検討することとし、地質の違いと水温との関係を定量化した。
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
    Date (from‐to) : 2013/04 -2018/03 
    Author : OZAKI KENICHI, SAYAMA Katsuhiko, NAKAMURA Futoshi, YAMANAKA Satoshi, INARI Naoki, HIRONAKA Yutaka
     
    We evaluated the effects of retention harvesting on ecosystem survices such as water and soil conservation, insect damage control and edible wild plants provision in a large-scale retention foresty experiment in fir plantations in Japan. For water and soil conservation services, water discharge and nitrogen runoff one year after harvest were affected by retention levels of broad-leaved tress in each experimental plot. For services to protect insect damage, avian predation on artificial caterpillars did not correlate with small bird density. Also, growth rate of todo-fir aphids (Cinara todocola) on fir seedlings differed with ant species that attended colonies of todo-fir aphids. For the provision of edible wild plants, we determined the change in the abundance of these plants after harvest and estimated the economic value of these wild plants.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
    Date (from‐to) : 2011/04 -2015/03 
    Author : NAKAMURA Futoshi, SUZUKI Toru, YAMAURA Yuichi, MORIMOTO Junko, NAGAYAMA Shigeya, NEGISHI Junjiro, AKASAKA Takumi
     
    This project focused on connectivity between various ecosystems, and examined the effects of restoration project. Among fish and aquatic insects, only high mobility groups could enhance species richness as spatial and hydrologic connectivity increased. Pond connectivity significantly affected the spatial variation of both population abundance and genetic diversity of the ninespine stickleback. We revealed millennium-scale dietary shifts of brown bears on the Hokkaido islands, Japan, using carbon, nitrogen, and sulfur stable isotope analysis, and found that human activities have caused an alteration in the trophic structure of brown bears. The meander and floodplains restoration project successfully increased the frequency of flooding over the floodplains and raised the water table, resulting in an increase of abundance and species richness of fish and invertebrate species and wetland vegetation areas.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
    Date (from‐to) : 2007 -2010 
    Author : NAKAMURA Futoshi, MORIMOTO Yukihiro, NATUHARA Yoshihiro, KAMADA Mahito, KOBAYASHI Tatsuaki, SHIBATA Shozo, YUMA Masahide, SHOJI Yasushi, MORIMOTO Junko
     
    We developed methodology of ecosystem evaluations regarding forests, rivers and agricultural lands. Also, we examined connectivity and historical changes of habitat mosaics and roles of biological legacies such as large wood in recovering processes of vegetation and stream biota. Fishes, invertebrates, plants, amphibians, mussels and mammals were selected as indicator species to evaluate restoration project based upon the results of monitoring and experiment. As for the economical and social aspects, restoration projects were analyzed, and social acceptance and future dimension were discussed.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
    Date (from‐to) : 2006 -2009 
    Author : MORIMOTO Yukihiro, NAKAMURA Futoshi, NATSUHARA Yoshihiro, KAMADA Mahito, KOBAYASHI Tatsuaki, YUMA Masahide, ASANO Kohta, IMANISHI Junichi, HASHIMOTO Hiroshi, ISAGI Yuji
     
    Recently, nature restoration projects are taking place in various regions in and outside Japan. For the purpose to contribute to develop the methods of restoration and the evaluation methods for the projects, we studied various ecosystems such as forests, rivers, wetlands and seacoast. Hierarchical approach was quite appropriate to deal with various targets. As a result, we could develop a lot of habitat models of species, and economical evaluation strategy.
  • 物質流入に伴う釧路湿原湖沼生態系の環境悪化と再生方策に関する研究
    日本学術振興会:科学研究費助成事業 特別研究員奨励費
    Date (from‐to) : 2006 -2007 
    Author : 中村 太士, 安 榮相
     
    釧路湿原流域は1960年代以降、大規模な農耕草地開発を受けて、湖沼周辺流域においても湿地・林地から農地へと転換されてきた。土地利用開発を受けた流域では、降雨時の地中浸透能の減少と地表流の増加、それに伴う湖沼への浮遊土砂、栄養塩類の流入・堆積、さらには湖沼の生態系変化と、連鎖的に湖環境が悪化すると考えられている。本年度(平成19年)の研究目的は、釧路湿原内湖の環境保全対策を確立するため、3湖(達古武湖・シラルトロ湖・塘路湖)における湖環境を悪化させる原因である栄養塩類(全窒素・全リン)の動態を把握及びシラルトロ湖の長期的な土砂堆積速度を明らかにすることである。 釧路湿原内の3湖における浮遊土砂と栄養塩類(全窒素・全リン)のモニタリングの結果、3湖の流出河川は釧路川と合流するため、増水時に釧路川の流水が湖へ流入(逆流)する現象が確認された。浮遊土砂及び全窒素・全リンの流入に伴う富栄養化、植物プランクトンの増加による透明度の低下が水草の種類・現存量を減少するという自然環境の劣化につながっていると考えられた。また、長期間の土砂堆積速度の実態を推定するためにシラルトロ湖底コアを採取し、湖底堆積物に発見された2層の火山灰判別と放射性同位体濃度(137Cs)を測定した。釧路湿原には2層の火山灰が多く分布しており、下層は駒ケ岳-c2(1694年)と上層は樽前-a(1739年)である。137Csは1960年代の大気核実験の際に放出された放射性降下物で、その降下量は1963年にピークがある。2つの火山灰と137Csにより過去300年間の土砂堆積実態を把握すると、流域開発が進んだ1963年以後は土砂堆積量が多く、人間活動が少なかったと思われる1963年以前に比べて約2倍であり、浅化は進んでいることが分かった。 本研究の結果により、今後釧路湿原の湖沼生態系保全のための基礎資料を提供できると考える。
  • A Method for Restoring the River Environment by Restoring Meanders
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2003 -2005 
    Author : WATANABE Yasuharu, YAMASHITA Shoji, HASEGAWA Kazuyoshi, NAKAMURA Futoshi
     
    Research was performed from 2003 to 2005 toward developing a method of reconnecting a cut-off meander on the Shibetsu River. Previous surveys at the test site showed that two-channel restoration in which the meander channel is reconnected while the straightened channel is maintained has promise with respect to flood control and environmental restoration. The findings are summarized here. 1)In movable-bed hydraulic model tests to reproduce bank erosion at river channels where mid-scale sand waves occur, the most suitable bed materials were those low in specific gravity and viscosity. 2)From field surveys, a method for studying the optimum channel centerline at the divergence and confluence of the two channels was developed based on the shapes of the restored channel and the straightened channel. When channel bifurcation is conducted, riverbed degradation at the confluence cannot be ignored. 3)At riverbank locations of sharply redirected flow, cherry salmon were observed in higher population densities and more diverse age breakdowns when fallen trees were placed than when no fallen trees were placed. Such placing is expected to be effective in fostering a favorable habitat for fishes. 4)By surveying the pollutant budget of the oxbow lake (the cut-off meander) and by constructing a model for estimating the water quality, the applicability of the model was confirmed. By developing a model for estimating the ground water level in wetlands, the effect of changes in river water level on changes in ground water level near the rivers were clarified.
  • Development of HEP in the process of ecological impact mitigation
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
    Date (from‐to) : 2002 -2005 
    Author : MORIMOTO Yukihiro, NATSUHARA Yoshihiro, NAKAMURA Futoshi, YAMAGUCHI Hirofumi, YUMA Masahide, IMANISHI Jun'ichi
     
    To contribute to strategic nature conservation and restoration, habitat evaluation methods and related subjects were studied at the field of sites, where some sorts of nature restoration or conservation activities are in the current issue of concern. Major results are as follows. (1) To restore small lake systems around Biwa lake, soil seed bank method considering temperature is a promising method to restore original vegetation such as Potamogeton malaianus, endangered species. (2) Aquatic vegetation such as wide width of reed communities are expected to be a nursery and refuge habitat for indigenous fish fauna such as Carassius auratus grandoculis, which is more tolerant to anaerobic conditions than exotic species such as black bass. (3) Habitat model was established in the case of Salamanders in dead water region, and several species. In the case of dynamic environment, such as meta-population theory is applied, simple HEP is not applicable, because PVA shows different results. (4) A new GAP analysis method using potential habitat estimation, using physiological properties, is developed in the case of Kyoto city area. (5) Genetic analyses of endangered aquatic species provided important information on regional characteristics on the distribution and propagation strategy of each target species of restoration. (6) Hierarchical consideration, stream system - segment - reach - habitat, for river nature restoration concept for nature restoration is applied to several projects. Multi - Before - After - Reference - Control - Impact sampling for the evaluation of nature restoration project is proposed Basic procedure for evaluation on nature restoration is proposed. (7) Desiccation process and restoration process in the Aral Sea crisis could be evaluated by the top predator species, pelicans, by the HSI model using satellite tracking.
  • Standardization of regional landscape information for Strategic Environmental Assessment
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2002 -2004 
    Author : NAKAGOSHI Nobukazu, ISAGI Yuji, KAMADA Mahito, NAKAMURA Futoshi, HARA Keitaro, MORIMOTO Yukihiro
     
    Several regional landscapes were investigated in different type of ecosystem, in different spatial scale, and gene flow among meta-population in an area. As for ecological studies, natural environments especially river landscapes, country sides, urban areas were selected for intensive study site, these areas were landscape ecologically studied from very wide scale as satellite image to chemical scale as DNA. Then, basing on the information, application of regional landscape information for Strategic Environmental Assessment was discussed among investigators of this project. For example, ecosystem functions were discussed as material flow in natural landscapes, water balance in catchments scale landscape, and fish meta-populations in an area, then conservation strategies of those landscapes were discussed. Especially, we tried to make effort finding out indicators for landscape function. As a result, an indicator of weed communities in countryside, and Ciconia boyciana : high lank species in a regional food web, biological indicators for urban greenery spaces were verified in each model research site. On the other hand, to valuate landscape function for Strategic Environmental Assessment, an extension tool for ArcGIS was developed as EcoGIS (a product from Central Research Institute of Electric Power Industry, 2004). Using the tool, ecotope maps which considered to be applied for Strategic Environmental Assessment were easily established basing on GIS system.
  • Theory application of ecosystem management
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 2001 -2003 
    Author : NAKAMURA Futoshi, YAMAMOTO Miho, KIKUCHI Shun-ichi, KAKIZAWA Hiroaki, IKEGAMI Yoshiyuki, KANEKO Masami
     
    Nakamura applied ecosystem management strategies primarily to a stream restoration project in the Shibetsu River. He developed assessment methodology that evaluates ecosystem structure and functions and further constructed a framework for restoring degraded river ecosystems including field survey and research planning methods. Kikuchi examined the roles of willow-dominant riparian forests in aquatic ecosystem conservation and identified the benefits of their seedling strategies under frequent flood disturbance regime. He also studied the relationship between physical environment of a stream and growth of an aquatic plant species, watercress. Kaneko constructed two geographic information system (GIS)-based database that support ecosystem management, which specifically are "Development of natural environment database assisting ecosystem conservation and restoration" and "Ecosystem conservation and management using GIS and the Internet". Owari constructed explicit knowledge database, which formalizes foresters' empirical knowledge, by using multimedia technologies (video and audio) and information technologies (Global positioning system and GIS). Ikegami applied landscape approaches to assess effects of highway construction on regional environment selecting 33 communities in northern Hokkaido and characterized the social and natural conditions of Otoineppu and Nakagawa towns in his GIS analyses. He also established a field method for wildlife survey using remotely sensed cameras. Kakizawa examined administrative structures that can take leadership in community development and surveyed perception of community development among private forest landowners. Yamamoto hypothesized that borders between forest and other landuses have continuously been shifted in accordance with fluctuating social and economic needs for the lands. He investigated an example in Hokkaido and described the mechanism of shifting landuse activities between agriculture and silviculture.
  • The effects of river regulations and land-use development on the regeneration of riparian tree species and ecological functions of riparian zone.
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B).
    Date (from‐to) : 1998 -2000 
    Author : NAKAMURA Futoshi, KIKUCHI Shun-ichi, YAJIMA Takashi
     
    There is a close relationship between physiotopes and tree species through habitat conditions. Chosenia arbutifolia, Toisus urubaniana and Poplus maximowiczii dominate upper and lower floodplains and the depositional bar, because these physiotopes, characterized by gravel soil and less soil moisture than other geomorphic surfaces, have establishment environments favored by these three species of Salicaceae trees. Dams for water regulation substantially alter the regeneration habitats of riparian species, thereby affecting their recruitment, composition and growth rate. This paper examines the effects of dams on the dynamics of riparian forests. First, the distribution of dominant riparian tree species was investigated in the Rekifune River, where no dams have been built, and their regeneration habitats were classified into five geomorphic surfaces based upon flooding frequency. C.arbutifolia and T.urubaniana appear on the most flood prone areas such as gravel bars and lower floodplains. P.maximowiczii also prefers coarse sediment, but establishes on upper floodplains. The late successional species, such as Ulmus davidiana var.japonica and Fraxinus mandshurica var.japonica, occur on stable surfaces referred to as terraces where sand and fine gravel make up the soil. Salix spp. dominates secondary channels. Second, the effects of dams on the regeneration process were examined in the Satsunai River where a flood control dam was completed in 1997. Spring floods in snowy regions mobilize riverbed sediment and create the moist, alluvial substrate ideal for seed germination. These habitats are essential for the recruitment of salicaceous species. Dams, in general, attenuate spring flooding and/or stabilize summer flows. This flow regime limits the development of gravel bars and reduces flood frequency. A decrease in flood frequency and magnitude may reduce the densities of pioneer species and shift species distribution from pioneer to late successional species.
  • Forest recovery after intense disturbance by volcanic activity
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 1996 -1998 
    Author : YAJIMA Takashi, CHA Joo Young, SHIMIZU Osamu, NAKAMURA Futoshi, SHIBUYA Masato, TAKAHASHI Kunihide
     
    We studied distribution and stand structure of a naturally regenerated Larix kaempferi stand on Mt. Komagatake, a volcano on the island of Hokkaido. Further, biomass allocation, dynamics of shoots, and seasonal changes of water potential were examined in saplings of L.kaempferi and some broadleaved trees. The stands on the mountain were composed of L.kaempferi, Betula spp. and Populus maximowiczii, and assortments of others. At 500m a. s. 1., the stand dominant height was 2.0 to 6.1m and basal area at ground level was 0.1 to 7.8 m^2/ha. These values indicate that the stand intensively restricted growth. The stands at higher altitudes were less developed than at lower altitudes in dominant height and basal area. The present L.kaempferi gradually started being established in the area between 500 and 700m a. s. 1. during 20 to 50 years after the eruption in 1929. Thereafter the number of the established L.kaempferi increased remarkably. We believed that seed dispersal from artificial forests of L.kaempferi that have been planted since 20 years after the eruption, and from the individuals that had invaded in the very early period, contributed to the increase of L.kaempferi trees. L.kaempferi allocated more biomass to leaves than broadleaved trees and less to roots which, however, had a larger ratio of fine roots. Although almost all of the shoots of L.kaempferi survived the growing season, broadleaved trees showed considerably high mortality ratios of shoots. These traits enable L.kaempferi seedlings to establish and to growth favorably. We considered that broadleaved trees could have persisted their population by sprouting. From the results of examining water potential of trees, we regarded L.kaempferi as a drought-tolerant tree, which can maintain physiological ability even under the low water potential, however, P.maximowiczii can be regarded as a drought-avoiding tree which tend to retain high water potential to sustain favorable physiological activity
  • Chronological Study on Forested Watershed Changes due to sediment movement by forest age analysis
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 1996 -1997 
    Author : ARAYA Tohru, KIKUCHI Shunichi, SHIMIZU Osamu, YAJIMA Takshi, NAKAMURA Futoshi
     
    Chronological analysis of geomorphic surfaces using forest ages, radiocarbon dates or tephra dates is an effective method for investigating geomorphic history of watersheds, and even for understanding spatial and temporal characteristics of sediment movement processes within the watersheds. Summarized results of this study are as follows : 1) We examined sediment routing in the Saru River basin. Tephrochronological analysis of hil1slopes showed long-term rates of sediment production caused by landslides. Volume of reservoir sedimentation and age distribution of forests established on sediment in the reservoirs were analyzed, indicating sediment yields from upstream basins. 2) Regeneration dynamics of riparian forests were examined along the Tokachi River. Analysis of species composition and tree age structure of the riparian forests revealed that the magnitude of sediment movement associated with flood events controlled the extent of disturbance and regeneration of riparian forests, creating a mosaic distributional pattern of forest patches in the riparian zone. 3) Debris flow history was researched at the alluvial fan head on Rishiri Island. Tree-ring chronology obtained from living trees was used to cross-date the establishment and death of the trees which were buried by debris flows of indeterminate ages. Results indicated two clusters of the debris-flow dates in the 1870s and the early l950s. 4) Radiocarbon dates and stratigraphic analysis of volcanic mudflow deposits provided new findings of mudflow occurrences in Mount Tokachi Volcano and Mount Meakan Volcano.
  • Developments of principles and methods to keep ecological functions of riparian forests
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 1996 -1997 
    Author : NAKAMURA Futoshi, KURIYAMA Kouichi, KIKUCHI Shunichi, YAJIMA Takashi
     
    We examined sediment routing system in a basin and regeneration process of riparian forests in order to present a framework for keeping ecological functions in stream management. A time lag between sediment production and transport promotes rapid aggradation and degradation of a streambed, resulting in creating terraced lateral deposits. These laterl deposits and associated braided pattern are clearly observed in a unconstrained reach. This reach has secondary and abandoned channels, lateral bars and floodplains, which provide regeneration sites for many species requiring a variety of moisture, substrate, and disturbance frequency. Once bare sites are created, tree seedlings are wstablished, resulting in uniformeed-, even-aged forests. Yhe substrate and stream landforms are closely correlated and we could explain the distribution of dominant tree species along the elevation gradient in the Tokachi River. The ecological functions of riparian forests were examined especially on shading and providing fish habitat. The shading by riparian forest crown was examined by heat-budgets and by statistical analysis, and them compared to verify the accuracy of regression analysis. The fish habitat ws investigated as a basis of multi-scale approach. These results indicated the importance of riparian forest, and difference in factors controlling fish abundance between scales. We focused on a revegetation method covering the site with boulders (stone-mulching), which improve site conditions by keeping soil moisture high and soil temperature low. The results proved that this method is very effective to improve dry stress and promotes an increase in growth of reparian trees.
  • Influence of land-use development on suspended sediment and wetland vegetation in Kushiro Marsh
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (B)
    Date (from‐to) : 1995 -1997 
    Author : NAKAMURA Futoshi, KURIYAMA Kouichi, YAJIMA Takashi
     
    Wetlands' effects on hydrology, water quality, and wildlife habitat are internationally recognized. We examined the influences of channelization on discharge of suspended sediment and wetland vegetation in Hokkaido, northern Japan. The impact of river channelization was confirmed not only by the sediment gudgets but also by river aggradation or degradation lafter the channelization and by the resultant vegetational changes. The budgets of suspended sediment demonstrated that wash load was the predominant component accounting for 95% of the total suspended load delivered into the wetland. This suspended sediment was primarily transported into the wetland by floding associated with the heavy rainfall. 25% of the wash load and 75% of the suspended bed material load were deposited in the channelized reach, which produced aggradation of about 2 m at the end of the reach. A shorting of the length of the channel, due to channelization of a meandering river, steepened the slope and enhanced the stream power to transport sediment. This steepening shifted the depositional zones of fine sediment 5km downstream and aggraded the riverbed. The aggradation reduced the carrying capacity of the channel and caused sediment ladened water to flood over the wetlands. the fine sediment accumulated on the wetlands gradually altered the edaphic conditions and wetland bvegetation. Salix spp.and Artemisis princeps dominate the sites representing a high water-level fluctuation and high total nitrogen, and low redox potential of wetlands' ground water. These sites are more evidence indicating taht the present condition is far different from normal. Orifinal vegetation such as sedges and Alunus japonica sere disappearing from the adjacent areas of the river channel and were being replaced by willow trees.
  • 流域(森林・河川・湿地・氾濫原)における自然再生の理論と技術の構築
    Date (from‐to) : 1997
  • DEVELOPING AND STANDARDIZATION OF BASIC METHODS FOR ANALYSIS OF LANDSCAPE SYSTEM
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
    Date (from‐to) : 1995 -1996 
    Author : NAKAGOSHI Nobukazu, NEHIRA Kunito, NUMATA Makoto, NAKAMURA Futoshi, NAKAMURA Toshihiko, KAMITANI Tomohiko
     
    Studies for develcping and standardization of methods for analysis of landscape system were carried out in the representaive areas in Japan. The recent changes of landscapes were rapid in farm villages, especially in mountain farm villages. The vegetation and landform dynamics in watersheds were summarized in Hokkaido, Honshu and Shikoku. Inner structure of ecotopes of secondary grasslands and alpine vegetation were clarified by functional and structural aspects. Terrestrial and riparian landscapes were generally standardized in 1 : 25,000 scale, but aquatic landscapes were not able to summarize in this scale. GIS was also introduced to built up data-base in landscape system of several areas.
  • Landscape Assessment Methods of Agro-Forestory Land
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for international Scientific Research
    Date (from‐to) : 1994 -1995 
    Author : ASAKAWA Shoichiro, AHERN Jack F., FABOS Julius Gy., AIKO Tetuya, NAKAMURA Futoshi, YAZAWA Masao, ISHII Yutaka
     
    Professor Jack Ahern was invited to HOkkaido University and Proffessor Ishii, Associate Professor Nakamura and Professor Asakawa visited The University of Massachusetts, Amherst in connection with this research. Through the meetings, which were held at the both Universities, the members of the research have had valuable discussions regarding comparisons of land use and landscape assessments between Japan and the U.S.A.. The especially focused on Hokkaido and Massachusetts. Based on the discussions and studies which have been carried out by each member, we are going to make a report. The subjects included are as follows ; (1)Land use, forest and forest regulation -A comparative study between Massachusetts, Baden-Wuerttemberg and Hokkaido- (2)Comparative studies of land use and landscape changes between metropolitan areas in Hokkaido and Massachusetts (3)Structure and function of riparian zone implications for Japanese river management (4)Visual compatibility and assessments of urban fringe landscapes based on a case study in the northern part of Sapporo city (5)Problems and possibilities of exploring landscape assessment methods which are suitable in Japan
  • 森林時空間情報解析による火山山麓変動履歴に関する研究
    日本学術振興会:科学研究費助成事業 一般研究(B)
    Date (from‐to) : 1994 -1994 
    Author : 新谷 融, 菊池 俊一, 清水 収, 矢島 崇, 中村 太士
     
    北海道内の代表的火山山麓を対象に、森林時空間情報である樹木群落齢構造、埋木年輪幅、埋木^<14>Cなどを用いて、火山活動の要因とその年代推定を行ったところ、これら新情報の有効性が認められた。1.古期火山利尻山山麓のエゾ・トドマツ林と土石流扇状地氾濫源の森林構造の相異から、1850年頃の利尻山山体崩壊とその後の二次的土石流発生が推測されるとともに、この氾濫原理没埋木年輪を用いたクロスデ-ティングの有効性が認められた。2.十勝岳では既往泥流堆積物中の埋木^<14>C年代から200、1000〜1300yB.P.などの泥流発生が明らかにされ、さらにエゾ(アカエゾ)・トドマツ林の構造から1700年頃の溶岩流(中央火口丘)、1800年頃の火山泥流とともに、小松原原生林が1857年溶岩流(焼山・摺鉢火口丘)と同時に起こった山腹水蒸気爆発・泥流によるものであることなどが明らかにされた。3.有珠山は1910年水蒸気爆発・明治新山形成期にドロノキ・ハンノキを中心とした先駆広葉樹林が形成されたが、これと同様に広葉樹主体の森林構造を有する駒ケ岳は、火砕流を主として1640、1856、1929年の火山活動により山麓が激変した。この駒ケ岳森林構造(自然再生林)を検討した結果、種数・密度・多様度は増大中であり、1929堆積物優占種は先駆樹(ヤナギ・ドロノキ)が主体であるが1640年ではナラ・カエデなどの後継樹に推移し、またAo層厚も0.2、4、7cmと増大するなど、樹木群落と地表表土の推移過程の関連性や堆積物化学物質含有量の相違から地表形成要因の相違が示唆された。4.樽前山では1669、1739年に降灰を中心に森林が激変しているが、かつて1940年頃まで広域に分布していたとされるエゾ・マツ純林が同齢構造(1931坂井)を有していたことから1739年噴火とくに火砕流によるものと結論された。
  • STRUCTURE AND FUNCTION OF RIPARIAN ZONE AND IMPLICATIONS FOR JAPANESE RIVER MANAGEMENT
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for General Scientific Research (C)
    Date (from‐to) : 1993 -1994 
    Author : NAKAMURA Futoshi, KIKUCHI Shun-ichi, YAJIMA Takashi
     
    This report describes the ecological structure and function of riparian zone which vary with spatial scale. The riparian zone consists of valley floor landform and riparian vegetation. The functions discussed are attenuation of sunlight energy, input of leaves and needles, contribution of woody debris to streams, and retention of flowing material out of transport. These primary functions directly or indirectly influence water and sediment qualities of streams, bars and floodplains. Shading provided by tree crowns over the stream strongly influences water temperature and primary production in lotic ecosystems. Litter falling into streams is a critical food resource for stream organisms, especially in forested headwater streams. Coarse woody debris supplied from hillslopes and floodplains create storage sites for organic and inorganic matters and enhance habitat diversity for aquatic biota. Moreover, stems and roots of riparian vegetation comb inorganic and organic matter transported from upstream, increasing the soil nutrients of floodplain deposits. Variation in valley floor width plays an important role in retaining materials transported in stream water by increaxing hydraulic and geomorphic complesity. Generally, these functions diminish with an increase in watershed area although some functions are kept in floodplains of large rivers. The main reason for this longitudinal variation is due to changes in the relative size of riparian trees and the stream channel. The new river management policy should emphasize the ecological functions of the riparian zone. Finally, the authors proposes river restoration planning by preserving or creating landscape elements based on the concepts of sustaining physical and ecological linkages.
  • Regeneration dynamics and meintenance mechanism of forest community
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Co-operative Research (A)
    Date (from‐to) : 1992 -1994 
    Author : YAMAMOTO Shinichi, ASANO Tohru, KAWAGUCHI Hideyuki, NAKAMURA Futoshi, KANZAKI Mamoru, IWASA Yoh
     
    1)Gap-regeneration dynamics of different forest types of Japan was investigated and gap-disturbance regime of these forest types was clarified.Also, gap-regeneration behavior of major tree species in these forest types was clarified and evaluated.2)Forest community dynamics were studied in a 6 ha permanent plot of a species rich, old-growth, temperate deciduous forest in Ogawa Forest Reserve, central Japan.The turnover time of population is positively correlated with the maximum dbh size of the species, indicating the slow change of the population of large sized species.3)The wave regeneration of forest trees is studied theoretically in model populations with a lattice structure.Two-dimensional models tend to produce more regular wave regenerating patterns than one-dimensional models.4)The effects of Sika deer(Cervus nippon)browsing on the regeneration of pioneer species were studied in relation to canopy gaps in a warm temperate evergreen oak fofest in Kasurayama, Nara City.Successful regeneration of a pioneer, Zanthoxylum ailanthoides, occurred for several years even after two major wind disturbances during the past 90 years.This may be due to less browsing pressure from the deer.5)Spatial distribution of natural regenerating trees were measured in a Pinus thunbergii plantation on Mt.Tanakami, Japan.The distribution of saplings and seedlings of barochores, anemochores, and coppicing species was especially clustered near their mother trees.
  • FOREST DISTURBANCE BY THE 1926 MUDFLOW AND REVEGETATION PROCESSES AT MT.TOKACHI VOLCANO
    Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for General Scientific Research (C)
    Date (from‐to) : 1991 -1992 
    Author : YAJIMA Takashi, NAKAMURA Futoshi, SHIMIZU Osamu, SHIBUYA Masato
     
    The 1926 mudflow at Mt.Tokachi Volcano created a vast, bare land mass with heterogeneous and edaphic conditions. Forests were regenerated mainly by seedings supplied from remaining vagetation islands and surrounding areas. Vagetative regrowth was possible in downstream and boundary areas of the mudflow where forests suffered light damage. Revegetated forests display a mosaic structure, consisting of small or large elongated patches. Atands can be classified by dominant soecies, such as Picea glehnii, P.jezoensis, Abies sachalinensis, and betula spp. Pure Betula stands are found at the boundary areas of the mudflow where fine sediment was deposited. Picea glehnii stands were established in the central areas of bounder-rich soil deposits. Dwarf bamboo(Sasa spp.) dominated the floor of Betula stands, and it is likely that its rapid recovery playd an important role in forming Betula stands. Soil analysis clearly indicated the strong linkage between edaphic conditions and stand types. We concluded that differences in atand structures of revegetated forests could be attributed the heterogeneous site conditions created by the mudflow.
  • 山地渓流における河畔林水温維持効果に関する熱収支的考察
    日本学術振興会:科学研究費助成事業 奨励研究(A)
    Date (from‐to) : 1989 -1989 
    Author : 中村 太士
  • 河川地形の違いによる河畔林生態系の比較研究
    日本学術振興会:科学研究費助成事業 奨励研究(A)
    Date (from‐to) : 1988 -1988 
    Author : 中村 太士
  • 可畔林構造の違いによる河川水温の変動に関する研究
    日本学術振興会:科学研究費助成事業 奨励研究(A)
    Date (from‐to) : 1987 -1987 
    Author : 中村 太士
  • 河畔林の破壊・成立に伴う水辺環境の変化に関する研究
    日本学術振興会:科学研究費助成事業 奨励研究(A)
    Date (from‐to) : 1986 -1986 
    Author : 中村 太士
  • コンピュータによる立体的斜面形態区分
    日本学術振興会:科学研究費助成事業 奨励研究(A)
    Date (from‐to) : 1985 -1985 
    Author : 中村 太士

Educational Activities

Teaching Experience

  • Inter-Graduate School Classes(General Subject):Natural and Applied Sciences
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 大学院共通科目
    キーワード : 生態系管理、流域保全、森林修復、自然資源政策、専門家、緑地管理
  • Advanced Integrated Landscape Management
    開講年度 : 2021
    課程区分 : 修士課程
    開講学部 : 農学院
    キーワード : 生態系管理、流域保全、森林修復、自然資源政策、専門家、緑地管理
  • Environment and People
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 全学教育
    キーワード : 湿地、泥炭地、湿原生態系、植物、動物、水生生物、タンチョウ、イトウ、保全と再生、水文、土壌、気象、津波、火山噴火、自然災害、水質、農業、土地利用、地球温暖化、熱帯泥炭
  • English Seminar
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 全学教育
    キーワード : 森林生態系の管理・保全、樹木の構造と性質、木質バイオマスの利活用
  • Freshman Seminar
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 全学教育
    キーワード : 組織構造、環境応答、強度、木質バイオマス、樹木の化学成分、オゾン・酸性雨、保全管理、森林管理、生物多様性、生態系サービス、国土保全、森林政策
  • Graduation Thesis
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 農学部
    キーワード : 森林科学に関する研究、主体性、まとめる能力、伝える能力、質問への応答能力、
  • Seminar on Forest ScienceⅠ
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 農学部
    キーワード : 森林科学、論理構築、発表技法、論文読解法、ゼミナール
  • Seminar on Forest ScienceⅡ
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 農学部
    キーワード : 森林科学、論理構築、発表技法、論文読解法、ゼミナール
  • Ecosystem Management
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 農学部
    キーワード : 生物多様性、生態系サービス、景観(ランドスケープ)、保護区、マトリックス、危機、復元、順応的管理
  • Practical Field Work on Silviculture and Forest Conservation
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 農学部
    キーワード : 流域保全、資源利用、森林と地域社会、自然災害の軽減・修復
  • Forest Planning
    開講年度 : 2021
    課程区分 : 学士課程
    開講学部 : 農学部
    キーワード : 持続可能な森林経営、林業法律、森林施業、森林?地、森林管理、森林施業、測樹学・森林航測

Social Contribution

Social Contribution

Others

  • 土木学会
  • 日本景観生態学会
  • 応用生態工学
  • 新砂防(砂防学会誌)
  • 地形(日本地形学連合学会誌)
  • 日本森林学会誌
  • 日本生態学会誌
  • Water Resources Research
  • River Research and Applications
  • Plant Species Biology
  • Plant Ecology
  • Landscape and Ecological Engineering
  • Journal of Vegetation Science
  • Journal of Environmental Management
  • Journal of Applied Ecology
  • Hydrological Processes
  • Geomorphology
  • Forest Ecology and Management
  • Environmental Management
  • Ecological Research
  • Ecological Monographs
  • Ecological Applications
  • Earth Surface Processes and Landforms
  • Canadian Journal of Forest Research
  • Biodiversity and Conservation
  • Aquatic Sciences


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